diff --git a/apn/data/erdos/Isolated/Erdos1020.erdos_1020.lean b/apn/data/erdos/Isolated/Erdos1020.erdos_1020.lean new file mode 100644 index 00000000..b52b5ed9 --- /dev/null +++ b/apn/data/erdos/Isolated/Erdos1020.erdos_1020.lean @@ -0,0 +1,36 @@ +import FormalConjecturesUtil + +/-! +# Erdős Problem 1020 + +*Reference:* [erdosproblems.com/1020](https://www.erdosproblems.com/1020) +-/ + +namespace Erdos1020 + +/-- The maximum number of edges in an `r`-uniform hypergraph on `n` vertices containing no +matching of size `k` (i.e. no `k` pairwise vertex-disjoint edges). -/ +noncomputable def f (n r k : ℕ) : ℕ := + open scoped Classical in + let candidates := + (((Finset.univ : Finset (Fin n)).powersetCard r).powerset).filter fun H ↦ + ¬ ∃ M : Finset (Finset (Fin n)), + M ⊆ H ∧ M.card = k ∧ (M : Set (Finset (Fin n))).PairwiseDisjoint id + candidates.sup Finset.card + +/-- +Let $f(n;r,k)$ be the maximal number of edges in an $r$-uniform hypergraph which contains no set of $k$ many independent edges. + +For all $r\geq 3$,\[f(n;r,k)=\max\left(\binom{rk-1}{r}, \binom{n}{r}-\binom{n-k+1}{r}\right).\] + +Note: the displayed formula is stated on the standard Erdős matching conjecture range +`k ≥ 1` and `n ≥ r*k - 1`; with fully unrestricted `n` the equality is trivially false +(e.g. `r = 3`, `k = 2`, `n = 4`), and for `n < r*k - 1` the source remarks the problem +is trivial (the complete `r`-uniform hypergraph has no `k`-matching). +-/ +theorem erdos_1020 : + ∀ (r : ℕ), 3 ≤ r → ∀ n k : ℕ, 0 < k → r * k - 1 ≤ n → + f n r k = max ((r * k - 1).choose r) (n.choose r - (n - k + 1).choose r) := by + sorry + +end Erdos1020 diff --git a/apn/data/erdos/Isolated/Erdos104.erdos_104.lean b/apn/data/erdos/Isolated/Erdos104.erdos_104.lean new file mode 100644 index 00000000..f490050b --- /dev/null +++ b/apn/data/erdos/Isolated/Erdos104.erdos_104.lean @@ -0,0 +1,35 @@ +import FormalConjecturesUtil + +/-! +# Erdős Problem 104 + +*Reference:* [erdosproblems.com/104](https://www.erdosproblems.com/104) +-/ + +open Filter +open scoped EuclideanGeometry + +namespace Erdos104 + +open EuclideanGeometry + +/-- The number of distinct unit circles containing at least three points of `P`. -/ +noncomputable def unitCircleCount (P : Finset ℝ²) : ℕ := + Set.ncard {s : Sphere ℝ² | s.radius = 1 ∧ 3 ≤ {p ∈ (P : Set ℝ²) | p ∈ s}.ncard} + +/-- The set of unit-circle counts attained by configurations of `n` points in the plane. -/ +noncomputable def possibleUnitCircleCounts (n : ℕ) : Set ℕ := + {k | ∃ P : Finset ℝ², P.card = n ∧ unitCircleCount P = k} + +/-- The maximum number of qualifying unit circles attained by a configuration of `n` points. -/ +noncomputable def maxUnitCircleCount (n : ℕ) : ℕ := + sSup (possibleUnitCircleCounts n) + +/-- +Given $n$ points in $\mathbb{R}^2$ the number of distinct unit circles containing at least three points is $o(n^2)$. +-/ +theorem erdos_104 : + (fun n : ℕ => (maxUnitCircleCount n : ℝ)) =o[atTop] (fun n : ℕ => (n : ℝ) ^ 2) := by + sorry + +end Erdos104 diff --git a/apn/data/erdos/Isolated/Erdos1083.erdos_1083.lean b/apn/data/erdos/Isolated/Erdos1083.erdos_1083.lean new file mode 100644 index 00000000..615b6352 --- /dev/null +++ b/apn/data/erdos/Isolated/Erdos1083.erdos_1083.lean @@ -0,0 +1,30 @@ +import FormalConjecturesUtil + +/-! +# Erdős Problem 1083 + +*Reference:* [erdosproblems.com/1083](https://www.erdosproblems.com/1083) +-/ + +open Filter + +namespace Erdos1083 + +/-- +The minimum number of distinct distances determined by an $n$-point subset of +$d$-dimensional Euclidean space. +-/ +noncomputable def f (d n : ℕ) : ℕ := + sInf {m : ℕ | ∃ points : Finset (EuclideanSpace ℝ (Fin d)), + points.card = n ∧ distinctDistances points = m} + +/-- +Let $d\geq 3$, and let $f_d(n)$ be the minimal $m$ such that every set of $n$ points in $\mathbb{R}^d$ determines at least $m$ distinct distances. Estimate $f_d(n)$ - in particular, is it true that\[f_d(n)=n^{\frac{2}{d}-o(1)}?\] +-/ +theorem erdos_1083 : + (∀ d : ℕ, 3 ≤ d → ∃ o : ℕ → ℝ, o =o[atTop] (1 : ℕ → ℝ) ∧ + ∀ᶠ n : ℕ in atTop, + (f d n : ℝ) = (n : ℝ) ^ ((2 : ℝ) / (d : ℝ) - o n)) := by + sorry + +end Erdos1083 diff --git a/apn/data/erdos/Isolated/Erdos1159.erdos_1159.lean b/apn/data/erdos/Isolated/Erdos1159.erdos_1159.lean new file mode 100644 index 00000000..49e409ba --- /dev/null +++ b/apn/data/erdos/Isolated/Erdos1159.erdos_1159.lean @@ -0,0 +1,26 @@ +import FormalConjecturesUtil + +/-! +# Erdős Problem 1159 + +*Reference:* +- [erdosproblems.com/1159](https://www.erdosproblems.com/1159) +-/ + +open Configuration + +namespace Erdos1159 + +/-- +Determine whether there exists a constant $C>1$ such that the following holds. + +Let $P$ be a finite projective plane. Must there exist a set of points $S$ such that $1\leq \lvert S\cap \ell\rvert \leq C$ for all lines $\ell$? +-/ +theorem erdos_1159 : + (∃ C : ℕ, 1 < C ∧ + ∀ (P L : Type) (_ : Membership P L) (_ : Fintype P) (_ : Fintype L), + ∀ _ : ProjectivePlane P L, ∃ S : Set P, ∀ l : L, + 1 ≤ (S ∩ {p : P | p ∈ l}).ncard ∧ (S ∩ {p : P | p ∈ l}).ncard ≤ C) := by + sorry + +end Erdos1159 diff --git a/apn/data/erdos/Isolated/Erdos1206.erdos_1206.parts.i.lean b/apn/data/erdos/Isolated/Erdos1206.erdos_1206.parts.i.lean new file mode 100644 index 00000000..964d7d12 --- /dev/null +++ b/apn/data/erdos/Isolated/Erdos1206.erdos_1206.parts.i.lean @@ -0,0 +1,20 @@ +import FormalConjecturesUtil + +/-! +# Erdős Problem 1206 + +*Reference:* [erdosproblems.com/1206](https://www.erdosproblems.com/1206) +-/ + +namespace Erdos1206 + +/-- +Does $\{1,2^3,\ldots,N^3\}$ contain a Sidon set of size $\gg N$? +-/ +theorem erdos_1206.parts.i : + ∃ c : ℝ, 0 < c ∧ ∀ᶠ N in Filter.atTop, ∃ S : Finset ℕ, + S ⊆ (Finset.Icc 1 N).image (fun n => n ^ 3) ∧ + IsSidon (S : Set ℕ) ∧ c * (N : ℝ) ≤ (S.card : ℝ) := by + sorry + +end Erdos1206 diff --git a/apn/data/erdos/Isolated/Erdos1206.erdos_1206.parts.ii.lean b/apn/data/erdos/Isolated/Erdos1206.erdos_1206.parts.ii.lean new file mode 100644 index 00000000..6c8f056d --- /dev/null +++ b/apn/data/erdos/Isolated/Erdos1206.erdos_1206.parts.ii.lean @@ -0,0 +1,19 @@ +import FormalConjecturesUtil + +/-! +# Erdős Problem 1206 + +*Reference:* [erdosproblems.com/1206](https://www.erdosproblems.com/1206) +-/ + +namespace Erdos1206 + +/-- +Is there an infinite set $A\subset \mathbb{N}$ of positive density such that $\{a^3 : a\in A\}$ is a Sidon set? +-/ +theorem erdos_1206.parts.ii : + ∃ A : Set ℕ, A.Infinite ∧ 0 < A.lowerDensity ∧ + IsSidon ((fun a : ℕ => a ^ 3) '' A) := by + sorry + +end Erdos1206 diff --git a/apn/data/erdos/Isolated/Erdos1207.erdos_1207.lean b/apn/data/erdos/Isolated/Erdos1207.erdos_1207.lean new file mode 100644 index 00000000..769f98ce --- /dev/null +++ b/apn/data/erdos/Isolated/Erdos1207.erdos_1207.lean @@ -0,0 +1,33 @@ +import FormalConjecturesUtil + +/-! +# Erdős Problem 1207 + +*Reference:* [erdosproblems.com/1207](https://www.erdosproblems.com/1207) +-/ + +open Filter + +namespace Erdos1207 + +/-- A set is isosceles-free if no three distinct points in it form an isosceles triangle. -/ +def IsIsoscelesFree {α : Type*} [Dist α] (A : Set α) : Prop := + A.Triplewise fun x y z => ¬ IsIsosceles x y z + +/-- +`P d n` is the largest number such that every set of `n` points in Euclidean `d`-space has an +isosceles-free subset of at least that size. +-/ +noncomputable def P (d n : ℕ) : ℕ := + sInf {m : ℕ | ∃ S : Finset (EuclideanSpace ℝ (Fin d)), S.card = n ∧ + m = sSup {k : ℕ | ∃ A : Finset (EuclideanSpace ℝ (Fin d)), + A ⊆ S ∧ IsIsoscelesFree (A : Set (EuclideanSpace ℝ (Fin d))) ∧ A.card = k}} + +/-- +Let $P_d(n)$ be such that in any set of $n$ points in $\mathbb{R}^d$ there exist at least $P_d(n)$ many points which do not contain an isosceles triangle. Estimate $P_d(n)$ - in particular, is it true that\[P_2(n)0$? +-/ +theorem erdos_1207 : + (∃ c > (0 : ℝ), ∀ᶠ n : ℕ in atTop, (P 2 n : ℝ) < (n : ℝ) ^ (1 - c)) := by + sorry + +end Erdos1207 diff --git a/apn/data/erdos/Isolated/Erdos181.erdos_181.lean b/apn/data/erdos/Isolated/Erdos181.erdos_181.lean new file mode 100644 index 00000000..40e2d10d --- /dev/null +++ b/apn/data/erdos/Isolated/Erdos181.erdos_181.lean @@ -0,0 +1,27 @@ +import FormalConjecturesUtil + +/-! +# Erdős Problem 181 + +*Reference:* [erdosproblems.com/181](https://www.erdosproblems.com/181) +-/ + +namespace Erdos181 + +open SimpleGraph + +/-- The diagonal Ramsey number of a finite graph `G`: the least `N` such that every red-blue +colouring of the edges of the complete graph on `N` vertices contains a monochromatic copy of `G`. +A graph `R` records the red edges, and `Rᶜ` records the blue edges. -/ +noncomputable def diagonalRamseyNumber {α : Type*} [Fintype α] (G : SimpleGraph α) : ℕ := + sInf {N : ℕ | ∀ R : SimpleGraph (Fin N), G.IsContained R ∨ G.IsContained Rᶜ} + +/-- +Let $Q_n$ be the $n$-dimensional hypercube graph (so that $Q_n$ has $2^n$ vertices and $n2^{n-1}$ edges). Prove that\[R(Q_n) \ll 2^n.\] +-/ +theorem erdos_181 : + ∃ C > (0 : ℝ), ∀ n : ℕ, + (diagonalRamseyNumber (hypercube n) : ℝ) ≤ C * 2 ^ n := by + sorry + +end Erdos181 diff --git a/apn/data/erdos/Isolated/Erdos322.erdos_322.lean b/apn/data/erdos/Isolated/Erdos322.erdos_322.lean new file mode 100644 index 00000000..bbb1c8f4 --- /dev/null +++ b/apn/data/erdos/Isolated/Erdos322.erdos_322.lean @@ -0,0 +1,25 @@ +import FormalConjecturesUtil + +/-! +# Erdős Problem 322 + +*Reference:* [erdosproblems.com/322](https://www.erdosproblems.com/322) +-/ + +namespace Erdos322 + +/-- For `k ≥ 3`, the number of ordered representations of `n` as a sum of `k` many `k`th +powers of nonnegative integers. The bases can be restricted to the interval from `0` to `n`. -/ +def representationCount (k n : ℕ) : ℕ := + ((Finset.univ : Finset (Fin k → Fin (n + 1))).filter + (fun a ↦ ∑ i, (a i : ℕ) ^ k = n)).card + +/-- +Let $k\geq 3$ and $A\subset \mathbb{N}$ be the set of $k$th powers. What is the order of growth of $1_A^{(k)}(n)$, i.e. the number of representations of $n$ as the sum of $k$ many $k$th powers? Does there exist some $c>0$ and infinitely many $n$ such that\[1_A^{(k)}(n) >n^c?\] +-/ +theorem erdos_322 : + (∀ k : ℕ, 3 ≤ k → ∃ c > (0 : ℝ), + {n : ℕ | (n : ℝ) ^ c < representationCount k n}.Infinite) := by + sorry + +end Erdos322 diff --git a/apn/data/erdos/Isolated/Erdos431.erdos_431.lean b/apn/data/erdos/Isolated/Erdos431.erdos_431.lean new file mode 100644 index 00000000..26e8ce27 --- /dev/null +++ b/apn/data/erdos/Isolated/Erdos431.erdos_431.lean @@ -0,0 +1,21 @@ +import FormalConjecturesUtil + +/-! +# Erdős Problem 431 + +*Reference:* [erdosproblems.com/431](https://www.erdosproblems.com/431) +-/ + +open scoped Pointwise + +namespace Erdos431 + +/-- +Are there two infinite sets $A$ and $B$ such that $A+B$ agrees with the set of prime numbers up to finitely many exceptions? +-/ +theorem erdos_431 : + (∃ A B : Set ℕ, A.Infinite ∧ B.Infinite ∧ + (symmDiff (A + B) {p : ℕ | p.Prime}).Finite) := by + sorry + +end Erdos431 diff --git a/apn/data/erdos/Isolated/Erdos478.erdos_478.lean b/apn/data/erdos/Isolated/Erdos478.erdos_478.lean new file mode 100644 index 00000000..121234ee --- /dev/null +++ b/apn/data/erdos/Isolated/Erdos478.erdos_478.lean @@ -0,0 +1,23 @@ +import FormalConjecturesUtil + +/-! +# Erdős Problem 478 + +*Reference:* [erdosproblems.com/478](https://www.erdosproblems.com/478) +-/ + +namespace Erdos478 + +/-- +Let $p$ be a prime and\[A_p = \{ k! \pmod{p} : 1\leq k + (((Finset.Ico 1 p).image (fun k => Nat.factorial k % p)).card : ℝ) / p) + (Filter.atTop ⊓ Filter.principal {p : ℕ | p.Prime}) + (nhds (1 - 1 / Real.exp 1)) + := by + sorry + +end Erdos478 diff --git a/apn/data/erdos/Isolated/Erdos548.erdos_548.lean b/apn/data/erdos/Isolated/Erdos548.erdos_548.lean new file mode 100644 index 00000000..a7ae2afb --- /dev/null +++ b/apn/data/erdos/Isolated/Erdos548.erdos_548.lean @@ -0,0 +1,22 @@ +import FormalConjecturesUtil + +/-! +# Erdős Problem 548 + +*Reference:* [erdosproblems.com/548](https://www.erdosproblems.com/548) +-/ + +open SimpleGraph + +namespace Erdos548 + +/-- +Let $n\geq k+1$. Every graph on $n$ vertices with at least $\frac{k-1}{2}n+1$ edges contains every tree on $k+1$ vertices. +-/ +theorem erdos_548 : + ∀ (n k : ℕ), k + 1 ≤ n → ∀ G : SimpleGraph (Fin n), + ((k : ℚ) - 1) / 2 * n + 1 ≤ (G.edgeSet.ncard : ℚ) → + ∀ T : SimpleGraph (Fin (k + 1)), T.IsTree → T.IsContained G := by + sorry + +end Erdos548 diff --git a/apn/data/erdos/Isolated/Erdos571.erdos_571.lean b/apn/data/erdos/Isolated/Erdos571.erdos_571.lean new file mode 100644 index 00000000..2e40dbad --- /dev/null +++ b/apn/data/erdos/Isolated/Erdos571.erdos_571.lean @@ -0,0 +1,25 @@ +import FormalConjecturesUtil + +/-! +# Erdős Problem 571 + +*References:* +- [erdosproblems.com/571](https://www.erdosproblems.com/571) +-/ + +open Filter SimpleGraph + +namespace Erdos571 + +/-- +Show that for any rational $\alpha \in [1,2)$ there exists a bipartite graph $G$ such that\[\mathrm{ex}(n;G)\asymp n^{\alpha}.\] +-/ +theorem erdos_571 : + ∀ α : ℚ, 1 ≤ α → α < 2 → + ∃ q : ℕ, ∃ G : SimpleGraph (Fin q), G.IsBipartite ∧ + Asymptotics.IsTheta atTop + (fun n : ℕ => (extremalNumber n G : ℝ)) + (fun n : ℕ => (n : ℝ) ^ (α : ℝ)) := by + sorry + +end Erdos571 diff --git a/apn/data/erdos/Isolated/Erdos583.erdos_583.lean b/apn/data/erdos/Isolated/Erdos583.erdos_583.lean new file mode 100644 index 00000000..93b6ce83 --- /dev/null +++ b/apn/data/erdos/Isolated/Erdos583.erdos_583.lean @@ -0,0 +1,44 @@ +import FormalConjecturesUtil + +/-! +# Erdős Problem 583 + +*References:* +- [erdosproblems.com/583](https://www.erdosproblems.com/583) +- [Er71] Erdős, P., *Some unsolved problems in graph theory and combinatorial analysis*. + Combinatorial Mathematics and its Applications (Proc. Conf., Oxford, 1969) (1971), 97-109. +-/ + +open SimpleGraph + +namespace Erdos583 + +/-- +A subgraph `H` of `G` is a path subgraph if it is the subgraph traced out by a path in `G`, +i.e. a walk with no repeated vertices. +-/ +def IsPathSubgraph {V : Type*} {G : SimpleGraph V} (H : G.Subgraph) : Prop := + ∃ (u v : V) (p : G.Walk u v), p.IsPath ∧ H = p.toSubgraph + +/-- +`D` is a partition of `G` into edge-disjoint subgraphs: the edge sets of the members of `D` +are pairwise disjoint and their union is the edge set of `G`. +-/ +def IsDecomposition {V : Type*} (G : SimpleGraph V) (D : Finset G.Subgraph) : Prop := + Set.PairwiseDisjoint (D : Set G.Subgraph) (fun H ↦ H.edgeSet) ∧ + (⋃ H ∈ D, H.edgeSet) = G.edgeSet + +/-- +Every connected graph on $n$ vertices can be partitioned into at most $\lceil n/2\rceil$ +edge-disjoint paths. + +A problem of Erdős and Gallai. +-/ +theorem erdos_583 {V : Type*} [Fintype V] (G : SimpleGraph V) (hG : G.Connected) : + ∃ D : Finset G.Subgraph, + (∀ H ∈ D, IsPathSubgraph H) ∧ + IsDecomposition G D ∧ + D.card ≤ ⌈(Fintype.card V : ℚ) / 2⌉₊ := by + sorry + +end Erdos583 diff --git a/apn/data/erdos/Isolated/Erdos713.erdos_713.parts.i.lean b/apn/data/erdos/Isolated/Erdos713.erdos_713.parts.i.lean new file mode 100644 index 00000000..fd947fe3 --- /dev/null +++ b/apn/data/erdos/Isolated/Erdos713.erdos_713.parts.i.lean @@ -0,0 +1,29 @@ +import FormalConjecturesUtil + +/-! +# Erdős Problem 713 + +*References:* +- [erdosproblems.com/713](https://www.erdosproblems.com/713) +-/ + +open Filter SimpleGraph + +namespace Erdos713 + +open scoped Classical in +/-- +Is it true that, for every bipartite graph $G$, there exists some $\alpha\in [1,2)$ and $c>0$ such that\[\mathrm{ex}(n;G)\sim cn^\alpha?\] + +The condition that $G$ have at least two edges excludes degenerate forbidden graphs whose +extremal number is eventually zero, for which the displayed asymptotic with $c>0$ is impossible. +-/ +theorem erdos_713.parts.i : + ∀ (q : ℕ) (G : SimpleGraph (Fin q)), G.IsBipartite → 2 ≤ G.edgeFinset.card → + ∃ α c : ℝ, α ∈ Set.Ico 1 2 ∧ 0 < c ∧ + Asymptotics.IsEquivalent atTop + (fun n : ℕ => (extremalNumber n G : ℝ)) + (fun n : ℕ => c * (n : ℝ) ^ α) := by + sorry + +end Erdos713 diff --git a/apn/data/erdos/Isolated/Erdos713.erdos_713.parts.ii.lean b/apn/data/erdos/Isolated/Erdos713.erdos_713.parts.ii.lean new file mode 100644 index 00000000..0baaba39 --- /dev/null +++ b/apn/data/erdos/Isolated/Erdos713.erdos_713.parts.ii.lean @@ -0,0 +1,30 @@ +import FormalConjecturesUtil + +/-! +# Erdős Problem 713 + +*References:* +- [erdosproblems.com/713](https://www.erdosproblems.com/713) +-/ + +open Filter SimpleGraph + +namespace Erdos713 + +open scoped Classical in +/-- +Must $\alpha$ be rational? + +The same nondegeneracy condition on $G$ is used as in part (i). Rationality means that the real +number $\alpha$ lies in the image of the canonical embedding $\mathbb{Q}\to\mathbb{R}$. +-/ +theorem erdos_713.parts.ii : + ∀ (q : ℕ) (G : SimpleGraph (Fin q)), G.IsBipartite → 2 ≤ G.edgeFinset.card → + ∀ α c : ℝ, α ∈ Set.Ico 1 2 → 0 < c → + Asymptotics.IsEquivalent atTop + (fun n : ℕ => (extremalNumber n G : ℝ)) + (fun n : ℕ => c * (n : ℝ) ^ α) → + α ∈ Set.range ((↑) : ℚ → ℝ) := by + sorry + +end Erdos713 diff --git a/apn/data/erdos/Isolated/Erdos714.erdos_714.lean b/apn/data/erdos/Isolated/Erdos714.erdos_714.lean new file mode 100644 index 00000000..42847602 --- /dev/null +++ b/apn/data/erdos/Isolated/Erdos714.erdos_714.lean @@ -0,0 +1,23 @@ +import FormalConjecturesUtil + +/-! +# Erdős Problem 714 + +*References:* +- [erdosproblems.com/714](https://www.erdosproblems.com/714) +-/ + +open Filter SimpleGraph + +namespace Erdos714 + +/-- +Is it true that\[\mathrm{ex}(n; K_{r,r}) \gg n^{2-1/r}?\] +-/ +theorem erdos_714 : + (∀ r : ℕ, 2 ≤ r → ∃ c : ℝ, 0 < c ∧ ∀ᶠ n : ℕ in atTop, + c * (n : ℝ) ^ ((2 : ℝ) - 1 / (r : ℝ)) ≤ + (extremalNumber n (completeBipartiteGraph (Fin r) (Fin r)) : ℝ)) := by + sorry + +end Erdos714 diff --git a/apn/data/erdos/Isolated/Erdos773.erdos_773.lean b/apn/data/erdos/Isolated/Erdos773.erdos_773.lean new file mode 100644 index 00000000..88cb9e75 --- /dev/null +++ b/apn/data/erdos/Isolated/Erdos773.erdos_773.lean @@ -0,0 +1,23 @@ +import FormalConjecturesUtil + +/-! +# Erdős Problem 773 + +*Reference:* [erdosproblems.com/773](https://www.erdosproblems.com/773) +-/ + +namespace Erdos773 + +open Filter + +/-- +What is the size of the largest Sidon subset $A\subseteq\{1,2^2,\ldots,N^2\}$? Is it $N^{1-o(1)}$? +-/ +theorem erdos_773 : + (∀ ε > (0 : ℝ), ∀ᶠ N : ℕ in atTop, + (N : ℝ) ^ (1 - ε) ≤ + (Finset.maxSidonSubsetCard + (Finset.image (fun n : ℕ => n ^ 2) (Finset.Icc 1 N)) : ℝ)) := by + sorry + +end Erdos773 diff --git a/apn/data/erdos/Isolated/Erdos86.erdos_86.lean b/apn/data/erdos/Isolated/Erdos86.erdos_86.lean new file mode 100644 index 00000000..5f9b71d7 --- /dev/null +++ b/apn/data/erdos/Isolated/Erdos86.erdos_86.lean @@ -0,0 +1,23 @@ +import FormalConjecturesUtil + +/-! +# Erdős Problem 86 + +*Reference:* [erdosproblems.com/86](https://www.erdosproblems.com/86) +-/ + +open Filter SimpleGraph + +namespace Erdos86 + +/-- +Let $Q_n$ be the $n$-dimensional hypercube graph (so that $Q_n$ has $2^n$ vertices and $n2^{n-1}$ edges). Is it true that every subgraph of $Q_n$ with\[\geq \left(\frac{1}{2}+o(1)\right)n2^{n-1}\]many edges contains a $C_4$? +-/ +theorem erdos_86 : + (∀ ε : ℝ, 0 < ε → ∀ᶠ n : ℕ in atTop, ∀ H : SimpleGraph (Fin n → Bool), + H ≤ hypercube n → + (1 / 2 + ε) * n * 2 ^ (n - 1 : ℕ) ≤ (H.edgeSet.ncard : ℝ) → + cycleGraph 4 ⊑ H) := by + sorry + +end Erdos86 diff --git a/apn/data/erdos/Isolated/Erdos970.erdos_970.lean b/apn/data/erdos/Isolated/Erdos970.erdos_970.lean new file mode 100644 index 00000000..ffc49c64 --- /dev/null +++ b/apn/data/erdos/Isolated/Erdos970.erdos_970.lean @@ -0,0 +1,32 @@ +import FormalConjecturesUtil + +/-! +# Erdős Problem 970 + +*Reference:* [erdosproblems.com/970](https://www.erdosproblems.com/970) +-/ + +namespace Erdos970 + +/-- +`IsJacobsthalBound k m` says that every interval of `m` consecutive integers contains an +integer coprime to every positive natural number having at most `k` distinct prime factors. +-/ +def IsJacobsthalBound (k m : ℕ) : Prop := + ∀ n : ℕ, 0 < n → n.primeFactors.card ≤ k → + ∀ a : ℤ, ∃ i : ℕ, i < m ∧ (a + i).natAbs.Coprime n + +/-- +Jacobsthal's function, uniformly parametrized by the maximum number of distinct prime factors. +-/ +noncomputable def jacobsthalFunction (k : ℕ) : ℕ := + sInf {m : ℕ | IsJacobsthalBound k m} + +/-- +Let $h(k)$ be Jacobsthal's function, defined to as the minimal $m$ such that, if $n$ has at most $k$ prime factors, then in any set of $m$ consecutive integers there exists an integer coprime to $n$. Determine the order of magnitude of $h(k)$. In particular, is it true that\[h(k) \ll k^2?\] +-/ +theorem erdos_970 : + (∃ C > (0 : ℝ), ∀ k : ℕ, 0 < k → (jacobsthalFunction k : ℝ) ≤ C * k ^ 2) := by + sorry + +end Erdos970 diff --git a/apn/data/erdos/Sources/1020.lean b/apn/data/erdos/Sources/1020.lean new file mode 100644 index 00000000..a926c638 --- /dev/null +++ b/apn/data/erdos/Sources/1020.lean @@ -0,0 +1,37 @@ +import FormalConjecturesUtil + +/-! +# Erdős Problem 1020 + +*Reference:* [erdosproblems.com/1020](https://www.erdosproblems.com/1020) +-/ + +namespace Erdos1020 + +/-- The maximum number of edges in an `r`-uniform hypergraph on `n` vertices containing no +matching of size `k` (i.e. no `k` pairwise vertex-disjoint edges). -/ +noncomputable def f (n r k : ℕ) : ℕ := + open scoped Classical in + let candidates := + (((Finset.univ : Finset (Fin n)).powersetCard r).powerset).filter fun H ↦ + ¬ ∃ M : Finset (Finset (Fin n)), + M ⊆ H ∧ M.card = k ∧ (M : Set (Finset (Fin n))).PairwiseDisjoint id + candidates.sup Finset.card + +/-- +Let $f(n;r,k)$ be the maximal number of edges in an $r$-uniform hypergraph which contains no set of $k$ many independent edges. + +For all $r\geq 3$,\[f(n;r,k)=\max\left(\binom{rk-1}{r}, \binom{n}{r}-\binom{n-k+1}{r}\right).\] + +Note: the displayed formula is stated on the standard Erdős matching conjecture range +`k ≥ 1` and `n ≥ r*k - 1`; with fully unrestricted `n` the equality is trivially false +(e.g. `r = 3`, `k = 2`, `n = 4`), and for `n < r*k - 1` the source remarks the problem +is trivial (the complete `r`-uniform hypergraph has no `k`-matching). +-/ +@[category research open, AMS 5] +theorem erdos_1020 : + ∀ (r : ℕ), 3 ≤ r → ∀ n k : ℕ, 0 < k → r * k - 1 ≤ n → + f n r k = max ((r * k - 1).choose r) (n.choose r - (n - k + 1).choose r) := by + sorry + +end Erdos1020 diff --git a/apn/data/erdos/Sources/104.lean b/apn/data/erdos/Sources/104.lean new file mode 100644 index 00000000..ad55c961 --- /dev/null +++ b/apn/data/erdos/Sources/104.lean @@ -0,0 +1,36 @@ +import FormalConjecturesUtil + +/-! +# Erdős Problem 104 + +*Reference:* [erdosproblems.com/104](https://www.erdosproblems.com/104) +-/ + +open Filter +open scoped EuclideanGeometry + +namespace Erdos104 + +open EuclideanGeometry + +/-- The number of distinct unit circles containing at least three points of `P`. -/ +noncomputable def unitCircleCount (P : Finset ℝ²) : ℕ := + Set.ncard {s : Sphere ℝ² | s.radius = 1 ∧ 3 ≤ {p ∈ (P : Set ℝ²) | p ∈ s}.ncard} + +/-- The set of unit-circle counts attained by configurations of `n` points in the plane. -/ +noncomputable def possibleUnitCircleCounts (n : ℕ) : Set ℕ := + {k | ∃ P : Finset ℝ², P.card = n ∧ unitCircleCount P = k} + +/-- The maximum number of qualifying unit circles attained by a configuration of `n` points. -/ +noncomputable def maxUnitCircleCount (n : ℕ) : ℕ := + sSup (possibleUnitCircleCounts n) + +/-- +Given $n$ points in $\mathbb{R}^2$ the number of distinct unit circles containing at least three points is $o(n^2)$. +-/ +@[category research open, AMS 52] +theorem erdos_104 : + (fun n : ℕ => (maxUnitCircleCount n : ℝ)) =o[atTop] (fun n : ℕ => (n : ℝ) ^ 2) := by + sorry + +end Erdos104 diff --git a/apn/data/erdos/Sources/1083.lean b/apn/data/erdos/Sources/1083.lean new file mode 100644 index 00000000..00fe2cc5 --- /dev/null +++ b/apn/data/erdos/Sources/1083.lean @@ -0,0 +1,31 @@ +import FormalConjecturesUtil + +/-! +# Erdős Problem 1083 + +*Reference:* [erdosproblems.com/1083](https://www.erdosproblems.com/1083) +-/ + +open Filter + +namespace Erdos1083 + +/-- +The minimum number of distinct distances determined by an $n$-point subset of +$d$-dimensional Euclidean space. +-/ +noncomputable def f (d n : ℕ) : ℕ := + sInf {m : ℕ | ∃ points : Finset (EuclideanSpace ℝ (Fin d)), + points.card = n ∧ distinctDistances points = m} + +/-- +Let $d\geq 3$, and let $f_d(n)$ be the minimal $m$ such that every set of $n$ points in $\mathbb{R}^d$ determines at least $m$ distinct distances. Estimate $f_d(n)$ - in particular, is it true that\[f_d(n)=n^{\frac{2}{d}-o(1)}?\] +-/ +@[category research open, AMS 52] +theorem erdos_1083 : + (∀ d : ℕ, 3 ≤ d → ∃ o : ℕ → ℝ, o =o[atTop] (1 : ℕ → ℝ) ∧ + ∀ᶠ n : ℕ in atTop, + (f d n : ℝ) = (n : ℝ) ^ ((2 : ℝ) / (d : ℝ) - o n)) := by + sorry + +end Erdos1083 diff --git a/apn/data/erdos/Sources/1159.lean b/apn/data/erdos/Sources/1159.lean new file mode 100644 index 00000000..a3c77218 --- /dev/null +++ b/apn/data/erdos/Sources/1159.lean @@ -0,0 +1,27 @@ +import FormalConjecturesUtil + +/-! +# Erdős Problem 1159 + +*Reference:* +- [erdosproblems.com/1159](https://www.erdosproblems.com/1159) +-/ + +open Configuration + +namespace Erdos1159 + +/-- +Determine whether there exists a constant $C>1$ such that the following holds. + +Let $P$ be a finite projective plane. Must there exist a set of points $S$ such that $1\leq \lvert S\cap \ell\rvert \leq C$ for all lines $\ell$? +-/ +@[category research open, AMS 5 51] +theorem erdos_1159 : + (∃ C : ℕ, 1 < C ∧ + ∀ (P L : Type) (_ : Membership P L) (_ : Fintype P) (_ : Fintype L), + ∀ _ : ProjectivePlane P L, ∃ S : Set P, ∀ l : L, + 1 ≤ (S ∩ {p : P | p ∈ l}).ncard ∧ (S ∩ {p : P | p ∈ l}).ncard ≤ C) := by + sorry + +end Erdos1159 diff --git a/apn/data/erdos/Sources/1206.lean b/apn/data/erdos/Sources/1206.lean new file mode 100644 index 00000000..1e260532 --- /dev/null +++ b/apn/data/erdos/Sources/1206.lean @@ -0,0 +1,30 @@ +import FormalConjecturesUtil + +/-! +# Erdős Problem 1206 + +*Reference:* [erdosproblems.com/1206](https://www.erdosproblems.com/1206) +-/ + +namespace Erdos1206 + +/-- +Does $\{1,2^3,\ldots,N^3\}$ contain a Sidon set of size $\gg N$? +-/ +@[category research open, AMS 5 11] +theorem erdos_1206.parts.i : + ∃ c : ℝ, 0 < c ∧ ∀ᶠ N in Filter.atTop, ∃ S : Finset ℕ, + S ⊆ (Finset.Icc 1 N).image (fun n => n ^ 3) ∧ + IsSidon (S : Set ℕ) ∧ c * (N : ℝ) ≤ (S.card : ℝ) := by + sorry + +/-- +Is there an infinite set $A\subset \mathbb{N}$ of positive density such that $\{a^3 : a\in A\}$ is a Sidon set? +-/ +@[category research open, AMS 5 11] +theorem erdos_1206.parts.ii : + ∃ A : Set ℕ, A.Infinite ∧ 0 < A.lowerDensity ∧ + IsSidon ((fun a : ℕ => a ^ 3) '' A) := by + sorry + +end Erdos1206 diff --git a/apn/data/erdos/Sources/1207.lean b/apn/data/erdos/Sources/1207.lean new file mode 100644 index 00000000..bb0edfe1 --- /dev/null +++ b/apn/data/erdos/Sources/1207.lean @@ -0,0 +1,34 @@ +import FormalConjecturesUtil + +/-! +# Erdős Problem 1207 + +*Reference:* [erdosproblems.com/1207](https://www.erdosproblems.com/1207) +-/ + +open Filter + +namespace Erdos1207 + +/-- A set is isosceles-free if no three distinct points in it form an isosceles triangle. -/ +def IsIsoscelesFree {α : Type*} [Dist α] (A : Set α) : Prop := + A.Triplewise fun x y z => ¬ IsIsosceles x y z + +/-- +`P d n` is the largest number such that every set of `n` points in Euclidean `d`-space has an +isosceles-free subset of at least that size. +-/ +noncomputable def P (d n : ℕ) : ℕ := + sInf {m : ℕ | ∃ S : Finset (EuclideanSpace ℝ (Fin d)), S.card = n ∧ + m = sSup {k : ℕ | ∃ A : Finset (EuclideanSpace ℝ (Fin d)), + A ⊆ S ∧ IsIsoscelesFree (A : Set (EuclideanSpace ℝ (Fin d))) ∧ A.card = k}} + +/-- +Let $P_d(n)$ be such that in any set of $n$ points in $\mathbb{R}^d$ there exist at least $P_d(n)$ many points which do not contain an isosceles triangle. Estimate $P_d(n)$ - in particular, is it true that\[P_2(n)0$? +-/ +@[category research open, AMS 52] +theorem erdos_1207 : + (∃ c > (0 : ℝ), ∀ᶠ n : ℕ in atTop, (P 2 n : ℝ) < (n : ℝ) ^ (1 - c)) := by + sorry + +end Erdos1207 diff --git a/apn/data/erdos/Sources/181.lean b/apn/data/erdos/Sources/181.lean new file mode 100644 index 00000000..690db298 --- /dev/null +++ b/apn/data/erdos/Sources/181.lean @@ -0,0 +1,28 @@ +import FormalConjecturesUtil + +/-! +# Erdős Problem 181 + +*Reference:* [erdosproblems.com/181](https://www.erdosproblems.com/181) +-/ + +namespace Erdos181 + +open SimpleGraph + +/-- The diagonal Ramsey number of a finite graph `G`: the least `N` such that every red-blue +colouring of the edges of the complete graph on `N` vertices contains a monochromatic copy of `G`. +A graph `R` records the red edges, and `Rᶜ` records the blue edges. -/ +noncomputable def diagonalRamseyNumber {α : Type*} [Fintype α] (G : SimpleGraph α) : ℕ := + sInf {N : ℕ | ∀ R : SimpleGraph (Fin N), G.IsContained R ∨ G.IsContained Rᶜ} + +/-- +Let $Q_n$ be the $n$-dimensional hypercube graph (so that $Q_n$ has $2^n$ vertices and $n2^{n-1}$ edges). Prove that\[R(Q_n) \ll 2^n.\] +-/ +@[category research open, AMS 5] +theorem erdos_181 : + ∃ C > (0 : ℝ), ∀ n : ℕ, + (diagonalRamseyNumber (hypercube n) : ℝ) ≤ C * 2 ^ n := by + sorry + +end Erdos181 diff --git a/apn/data/erdos/Sources/322.lean b/apn/data/erdos/Sources/322.lean new file mode 100644 index 00000000..c0aa13cf --- /dev/null +++ b/apn/data/erdos/Sources/322.lean @@ -0,0 +1,26 @@ +import FormalConjecturesUtil + +/-! +# Erdős Problem 322 + +*Reference:* [erdosproblems.com/322](https://www.erdosproblems.com/322) +-/ + +namespace Erdos322 + +/-- For `k ≥ 3`, the number of ordered representations of `n` as a sum of `k` many `k`th +powers of nonnegative integers. The bases can be restricted to the interval from `0` to `n`. -/ +def representationCount (k n : ℕ) : ℕ := + ((Finset.univ : Finset (Fin k → Fin (n + 1))).filter + (fun a ↦ ∑ i, (a i : ℕ) ^ k = n)).card + +/-- +Let $k\geq 3$ and $A\subset \mathbb{N}$ be the set of $k$th powers. What is the order of growth of $1_A^{(k)}(n)$, i.e. the number of representations of $n$ as the sum of $k$ many $k$th powers? Does there exist some $c>0$ and infinitely many $n$ such that\[1_A^{(k)}(n) >n^c?\] +-/ +@[category research open, AMS 11] +theorem erdos_322 : + (∀ k : ℕ, 3 ≤ k → ∃ c > (0 : ℝ), + {n : ℕ | (n : ℝ) ^ c < representationCount k n}.Infinite) := by + sorry + +end Erdos322 diff --git a/apn/data/erdos/Sources/431.lean b/apn/data/erdos/Sources/431.lean new file mode 100644 index 00000000..f9cfc7b9 --- /dev/null +++ b/apn/data/erdos/Sources/431.lean @@ -0,0 +1,22 @@ +import FormalConjecturesUtil + +/-! +# Erdős Problem 431 + +*Reference:* [erdosproblems.com/431](https://www.erdosproblems.com/431) +-/ + +open scoped Pointwise + +namespace Erdos431 + +/-- +Are there two infinite sets $A$ and $B$ such that $A+B$ agrees with the set of prime numbers up to finitely many exceptions? +-/ +@[category research open, AMS 11] +theorem erdos_431 : + (∃ A B : Set ℕ, A.Infinite ∧ B.Infinite ∧ + (symmDiff (A + B) {p : ℕ | p.Prime}).Finite) := by + sorry + +end Erdos431 diff --git a/apn/data/erdos/Sources/478.lean b/apn/data/erdos/Sources/478.lean new file mode 100644 index 00000000..6bbf92f0 --- /dev/null +++ b/apn/data/erdos/Sources/478.lean @@ -0,0 +1,24 @@ +import FormalConjecturesUtil + +/-! +# Erdős Problem 478 + +*Reference:* [erdosproblems.com/478](https://www.erdosproblems.com/478) +-/ + +namespace Erdos478 + +/-- +Let $p$ be a prime and\[A_p = \{ k! \pmod{p} : 1\leq k + (((Finset.Ico 1 p).image (fun k => Nat.factorial k % p)).card : ℝ) / p) + (Filter.atTop ⊓ Filter.principal {p : ℕ | p.Prime}) + (nhds (1 - 1 / Real.exp 1)) + := by + sorry + +end Erdos478 diff --git a/apn/data/erdos/Sources/548.lean b/apn/data/erdos/Sources/548.lean new file mode 100644 index 00000000..fdbf8997 --- /dev/null +++ b/apn/data/erdos/Sources/548.lean @@ -0,0 +1,23 @@ +import FormalConjecturesUtil + +/-! +# Erdős Problem 548 + +*Reference:* [erdosproblems.com/548](https://www.erdosproblems.com/548) +-/ + +open SimpleGraph + +namespace Erdos548 + +/-- +Let $n\geq k+1$. Every graph on $n$ vertices with at least $\frac{k-1}{2}n+1$ edges contains every tree on $k+1$ vertices. +-/ +@[category research open, AMS 5] +theorem erdos_548 : + ∀ (n k : ℕ), k + 1 ≤ n → ∀ G : SimpleGraph (Fin n), + ((k : ℚ) - 1) / 2 * n + 1 ≤ (G.edgeSet.ncard : ℚ) → + ∀ T : SimpleGraph (Fin (k + 1)), T.IsTree → T.IsContained G := by + sorry + +end Erdos548 diff --git a/apn/data/erdos/Sources/571.lean b/apn/data/erdos/Sources/571.lean new file mode 100644 index 00000000..30389ac3 --- /dev/null +++ b/apn/data/erdos/Sources/571.lean @@ -0,0 +1,26 @@ +import FormalConjecturesUtil + +/-! +# Erdős Problem 571 + +*References:* +- [erdosproblems.com/571](https://www.erdosproblems.com/571) +-/ + +open Filter SimpleGraph + +namespace Erdos571 + +/-- +Show that for any rational $\alpha \in [1,2)$ there exists a bipartite graph $G$ such that\[\mathrm{ex}(n;G)\asymp n^{\alpha}.\] +-/ +@[category research open, AMS 5] +theorem erdos_571 : + ∀ α : ℚ, 1 ≤ α → α < 2 → + ∃ q : ℕ, ∃ G : SimpleGraph (Fin q), G.IsBipartite ∧ + Asymptotics.IsTheta atTop + (fun n : ℕ => (extremalNumber n G : ℝ)) + (fun n : ℕ => (n : ℝ) ^ (α : ℝ)) := by + sorry + +end Erdos571 diff --git a/apn/data/erdos/Sources/583.lean b/apn/data/erdos/Sources/583.lean new file mode 100644 index 00000000..597fabdd --- /dev/null +++ b/apn/data/erdos/Sources/583.lean @@ -0,0 +1,45 @@ +import FormalConjecturesUtil + +/-! +# Erdős Problem 583 + +*References:* +- [erdosproblems.com/583](https://www.erdosproblems.com/583) +- [Er71] Erdős, P., *Some unsolved problems in graph theory and combinatorial analysis*. + Combinatorial Mathematics and its Applications (Proc. Conf., Oxford, 1969) (1971), 97-109. +-/ + +open SimpleGraph + +namespace Erdos583 + +/-- +A subgraph `H` of `G` is a path subgraph if it is the subgraph traced out by a path in `G`, +i.e. a walk with no repeated vertices. +-/ +def IsPathSubgraph {V : Type*} {G : SimpleGraph V} (H : G.Subgraph) : Prop := + ∃ (u v : V) (p : G.Walk u v), p.IsPath ∧ H = p.toSubgraph + +/-- +`D` is a partition of `G` into edge-disjoint subgraphs: the edge sets of the members of `D` +are pairwise disjoint and their union is the edge set of `G`. +-/ +def IsDecomposition {V : Type*} (G : SimpleGraph V) (D : Finset G.Subgraph) : Prop := + Set.PairwiseDisjoint (D : Set G.Subgraph) (fun H ↦ H.edgeSet) ∧ + (⋃ H ∈ D, H.edgeSet) = G.edgeSet + +/-- +Every connected graph on $n$ vertices can be partitioned into at most $\lceil n/2\rceil$ +edge-disjoint paths. + +A problem of Erdős and Gallai. +-/ +@[category research open, AMS 5] +theorem erdos_583 {V : Type*} [Fintype V] (G : SimpleGraph V) (hG : G.Connected) : + ∃ D : Finset G.Subgraph, + (∀ H ∈ D, IsPathSubgraph H) ∧ + IsDecomposition G D ∧ + D.card ≤ ⌈(Fintype.card V : ℚ) / 2⌉₊ := by + sorry + +end Erdos583 diff --git a/apn/data/erdos/Sources/713.lean b/apn/data/erdos/Sources/713.lean new file mode 100644 index 00000000..9121f75d --- /dev/null +++ b/apn/data/erdos/Sources/713.lean @@ -0,0 +1,47 @@ +import FormalConjecturesUtil + +/-! +# Erdős Problem 713 + +*References:* +- [erdosproblems.com/713](https://www.erdosproblems.com/713) +-/ + +open Filter SimpleGraph + +namespace Erdos713 + +open scoped Classical in +/-- +Is it true that, for every bipartite graph $G$, there exists some $\alpha\in [1,2)$ and $c>0$ such that\[\mathrm{ex}(n;G)\sim cn^\alpha?\] + +The condition that $G$ have at least two edges excludes degenerate forbidden graphs whose +extremal number is eventually zero, for which the displayed asymptotic with $c>0$ is impossible. +-/ +@[category research open, AMS 5] +theorem erdos_713.parts.i : + ∀ (q : ℕ) (G : SimpleGraph (Fin q)), G.IsBipartite → 2 ≤ G.edgeFinset.card → + ∃ α c : ℝ, α ∈ Set.Ico 1 2 ∧ 0 < c ∧ + Asymptotics.IsEquivalent atTop + (fun n : ℕ => (extremalNumber n G : ℝ)) + (fun n : ℕ => c * (n : ℝ) ^ α) := by + sorry + +open scoped Classical in +/-- +Must $\alpha$ be rational? + +The same nondegeneracy condition on $G$ is used as in part (i). Rationality means that the real +number $\alpha$ lies in the image of the canonical embedding $\mathbb{Q}\to\mathbb{R}$. +-/ +@[category research open, AMS 5] +theorem erdos_713.parts.ii : + ∀ (q : ℕ) (G : SimpleGraph (Fin q)), G.IsBipartite → 2 ≤ G.edgeFinset.card → + ∀ α c : ℝ, α ∈ Set.Ico 1 2 → 0 < c → + Asymptotics.IsEquivalent atTop + (fun n : ℕ => (extremalNumber n G : ℝ)) + (fun n : ℕ => c * (n : ℝ) ^ α) → + α ∈ Set.range ((↑) : ℚ → ℝ) := by + sorry + +end Erdos713 diff --git a/apn/data/erdos/Sources/714.lean b/apn/data/erdos/Sources/714.lean new file mode 100644 index 00000000..f4552eb1 --- /dev/null +++ b/apn/data/erdos/Sources/714.lean @@ -0,0 +1,24 @@ +import FormalConjecturesUtil + +/-! +# Erdős Problem 714 + +*References:* +- [erdosproblems.com/714](https://www.erdosproblems.com/714) +-/ + +open Filter SimpleGraph + +namespace Erdos714 + +/-- +Is it true that\[\mathrm{ex}(n; K_{r,r}) \gg n^{2-1/r}?\] +-/ +@[category research open, AMS 5] +theorem erdos_714 : + (∀ r : ℕ, 2 ≤ r → ∃ c : ℝ, 0 < c ∧ ∀ᶠ n : ℕ in atTop, + c * (n : ℝ) ^ ((2 : ℝ) - 1 / (r : ℝ)) ≤ + (extremalNumber n (completeBipartiteGraph (Fin r) (Fin r)) : ℝ)) := by + sorry + +end Erdos714 diff --git a/apn/data/erdos/Sources/773.lean b/apn/data/erdos/Sources/773.lean new file mode 100644 index 00000000..a3c6f9a6 --- /dev/null +++ b/apn/data/erdos/Sources/773.lean @@ -0,0 +1,24 @@ +import FormalConjecturesUtil + +/-! +# Erdős Problem 773 + +*Reference:* [erdosproblems.com/773](https://www.erdosproblems.com/773) +-/ + +namespace Erdos773 + +open Filter + +/-- +What is the size of the largest Sidon subset $A\subseteq\{1,2^2,\ldots,N^2\}$? Is it $N^{1-o(1)}$? +-/ +@[category research open, AMS 11] +theorem erdos_773 : + (∀ ε > (0 : ℝ), ∀ᶠ N : ℕ in atTop, + (N : ℝ) ^ (1 - ε) ≤ + (Finset.maxSidonSubsetCard + (Finset.image (fun n : ℕ => n ^ 2) (Finset.Icc 1 N)) : ℝ)) := by + sorry + +end Erdos773 diff --git a/apn/data/erdos/Sources/86.lean b/apn/data/erdos/Sources/86.lean new file mode 100644 index 00000000..7f33b673 --- /dev/null +++ b/apn/data/erdos/Sources/86.lean @@ -0,0 +1,24 @@ +import FormalConjecturesUtil + +/-! +# Erdős Problem 86 + +*Reference:* [erdosproblems.com/86](https://www.erdosproblems.com/86) +-/ + +open Filter SimpleGraph + +namespace Erdos86 + +/-- +Let $Q_n$ be the $n$-dimensional hypercube graph (so that $Q_n$ has $2^n$ vertices and $n2^{n-1}$ edges). Is it true that every subgraph of $Q_n$ with\[\geq \left(\frac{1}{2}+o(1)\right)n2^{n-1}\]many edges contains a $C_4$? +-/ +@[category research open, AMS 5] +theorem erdos_86 : + (∀ ε : ℝ, 0 < ε → ∀ᶠ n : ℕ in atTop, ∀ H : SimpleGraph (Fin n → Bool), + H ≤ hypercube n → + (1 / 2 + ε) * n * 2 ^ (n - 1 : ℕ) ≤ (H.edgeSet.ncard : ℝ) → + cycleGraph 4 ⊑ H) := by + sorry + +end Erdos86 diff --git a/apn/data/erdos/Sources/970.lean b/apn/data/erdos/Sources/970.lean new file mode 100644 index 00000000..729a646c --- /dev/null +++ b/apn/data/erdos/Sources/970.lean @@ -0,0 +1,33 @@ +import FormalConjecturesUtil + +/-! +# Erdős Problem 970 + +*Reference:* [erdosproblems.com/970](https://www.erdosproblems.com/970) +-/ + +namespace Erdos970 + +/-- +`IsJacobsthalBound k m` says that every interval of `m` consecutive integers contains an +integer coprime to every positive natural number having at most `k` distinct prime factors. +-/ +def IsJacobsthalBound (k m : ℕ) : Prop := + ∀ n : ℕ, 0 < n → n.primeFactors.card ≤ k → + ∀ a : ℤ, ∃ i : ℕ, i < m ∧ (a + i).natAbs.Coprime n + +/-- +Jacobsthal's function, uniformly parametrized by the maximum number of distinct prime factors. +-/ +noncomputable def jacobsthalFunction (k : ℕ) : ℕ := + sInf {m : ℕ | IsJacobsthalBound k m} + +/-- +Let $h(k)$ be Jacobsthal's function, defined to as the minimal $m$ such that, if $n$ has at most $k$ prime factors, then in any set of $m$ consecutive integers there exists an integer coprime to $n$. Determine the order of magnitude of $h(k)$. In particular, is it true that\[h(k) \ll k^2?\] +-/ +@[category research open, AMS 11] +theorem erdos_970 : + (∃ C > (0 : ℝ), ∀ k : ℕ, 0 < k → (jacobsthalFunction k : ℝ) ≤ C * k ^ 2) := by + sorry + +end Erdos970 diff --git a/apn/data/erdos/samples.jsonl b/apn/data/erdos/samples.jsonl index 00ae555d..ec8e0cff 100644 --- a/apn/data/erdos/samples.jsonl +++ b/apn/data/erdos/samples.jsonl @@ -142,3 +142,23 @@ {"id": "Erdos975.erdos_975.variants.n2_plus_1_strong", "source": "Sources/975.lean", "erdos_number": 975, "category_at_pin": "research solved", "answer_form": null} {"id": "Erdos975.erdos_975.variants.quadratic", "source": "Sources/975.lean", "excluded": "value-typed answer(sorry): the placeholder elaborates to a position-labeled sorryAx in the statement's type, so the statement cannot be closed (or even stated) without the paper's google.answer \"with_auxiliary\" machinery, and SafeVerify cannot score it", "erdos_number": 975, "category_at_pin": "research solved"} {"id": "Erdos975.erdos_975.variants.upper_bound", "source": "Sources/975.lean", "erdos_number": 975, "category_at_pin": "research solved", "answer_form": null} +{"id": "Erdos86.erdos_86", "source": "Sources/86.lean", "erdos_number": 86, "category_at_pin": "research open", "answer_form": null} +{"id": "Erdos104.erdos_104", "source": "Sources/104.lean", "erdos_number": 104, "category_at_pin": "research open", "answer_form": null} +{"id": "Erdos181.erdos_181", "source": "Sources/181.lean", "erdos_number": 181, "category_at_pin": "research open", "answer_form": null} +{"id": "Erdos322.erdos_322", "source": "Sources/322.lean", "erdos_number": 322, "category_at_pin": "research open", "answer_form": null} +{"id": "Erdos431.erdos_431", "source": "Sources/431.lean", "erdos_number": 431, "category_at_pin": "research open", "answer_form": null} +{"id": "Erdos478.erdos_478", "source": "Sources/478.lean", "erdos_number": 478, "category_at_pin": "research open", "answer_form": null} +{"id": "Erdos548.erdos_548", "source": "Sources/548.lean", "erdos_number": 548, "category_at_pin": "research open", "answer_form": null} +{"id": "Erdos571.erdos_571", "source": "Sources/571.lean", "erdos_number": 571, "category_at_pin": "research open", "answer_form": null} +{"id": "Erdos583.erdos_583", "source": "Sources/583.lean", "erdos_number": 583, "category_at_pin": "research open", "answer_form": null} +{"id": "Erdos713.erdos_713.parts.i", "source": "Sources/713.lean", "erdos_number": 713, "category_at_pin": "research open", "answer_form": null} +{"id": "Erdos713.erdos_713.parts.ii", "source": "Sources/713.lean", "erdos_number": 713, "category_at_pin": "research open", "answer_form": null} +{"id": "Erdos714.erdos_714", "source": "Sources/714.lean", "erdos_number": 714, "category_at_pin": "research open", "answer_form": null} +{"id": "Erdos773.erdos_773", "source": "Sources/773.lean", "erdos_number": 773, "category_at_pin": "research open", "answer_form": null} +{"id": "Erdos970.erdos_970", "source": "Sources/970.lean", "erdos_number": 970, "category_at_pin": "research open", "answer_form": null} +{"id": "Erdos1020.erdos_1020", "source": "Sources/1020.lean", "erdos_number": 1020, "category_at_pin": "research open", "answer_form": null} +{"id": "Erdos1083.erdos_1083", "source": "Sources/1083.lean", "erdos_number": 1083, "category_at_pin": "research open", "answer_form": null} +{"id": "Erdos1159.erdos_1159", "source": "Sources/1159.lean", "erdos_number": 1159, "category_at_pin": "research open", "answer_form": null} +{"id": "Erdos1206.erdos_1206.parts.i", "source": "Sources/1206.lean", "erdos_number": 1206, "category_at_pin": "research open", "answer_form": null} +{"id": "Erdos1206.erdos_1206.parts.ii", "source": "Sources/1206.lean", "erdos_number": 1206, "category_at_pin": "research open", "answer_form": null} +{"id": "Erdos1207.erdos_1207", "source": "Sources/1207.lean", "erdos_number": 1207, "category_at_pin": "research open", "answer_form": null} diff --git a/apn/data/erdos/subsets/target18.json b/apn/data/erdos/subsets/target18.json new file mode 100644 index 00000000..34705707 --- /dev/null +++ b/apn/data/erdos/subsets/target18.json @@ -0,0 +1,25 @@ +{ + "description": "The 18 Erdős problems from the 2026-08-25 autoformalization target run (epoch-research/autoformalization results/2026-08-25-erdos-target-run): problems absent from google-deepmind/formal-conjectures, autoformalized and gate-passed at FC 9cbe1d3c (1020 from hold/, the rest from submit/). 20 statements: 713 and 1206 each have two parts. Throwaway smoke-run subset -- a solve at a modest budget is a misformalization red flag.", + "ids": [ + "Erdos86.erdos_86", + "Erdos104.erdos_104", + "Erdos181.erdos_181", + "Erdos322.erdos_322", + "Erdos431.erdos_431", + "Erdos478.erdos_478", + "Erdos548.erdos_548", + "Erdos571.erdos_571", + "Erdos583.erdos_583", + "Erdos713.erdos_713.parts.i", + "Erdos713.erdos_713.parts.ii", + "Erdos714.erdos_714", + "Erdos773.erdos_773", + "Erdos970.erdos_970", + "Erdos1020.erdos_1020", + "Erdos1083.erdos_1083", + "Erdos1159.erdos_1159", + "Erdos1206.erdos_1206.parts.i", + "Erdos1206.erdos_1206.parts.ii", + "Erdos1207.erdos_1207" + ] +} diff --git a/configs/erdos-target18-smoke.yaml b/configs/erdos-target18-smoke.yaml new file mode 100644 index 00000000..03cbc94d --- /dev/null +++ b/configs/erdos-target18-smoke.yaml @@ -0,0 +1,86 @@ +# Schema reference for eval-set config: +# https://github.com/METR/hawk/blob/main/hawk/api/EvalSetConfig.schema.json +# +# THROWAWAY misformalization smoke run: the 18 Erdős problems autoformalized in +# the 2026-08-25 autoformalization target run (epoch-research/autoformalization +# results/2026-08-25-erdos-target-run; 20 statements -- 713 and 1206 have two +# parts each), vendored into apn/data/erdos on the erdos-target-smoke branch +# (stacked on PR #28). These are open problems: a solve at a modest $50/sample +# budget is a red flag that the statement was misformalized (too easy), not a +# mathematical breakthrough. +# +# COST (2 models x 20 statements x 1 epoch = 40 samples, $50/sample cap): +# Max: 40 x $50 = $2,000 hard ceiling; expected near max (open problems -- +# most samples should burn the cap without a solve). +retry_attempts: 0 + +tasks: + - package: git+ssh://git@github.com/epoch-research/LeanOpenProblems.git@erdos-target-smoke + name: apn + items: + - name: apn_erdos + args: + subset: target18 + +name: erdos-target18-smoke +epochs: 1 +models: + # Epoch model wrappers (bypass middleman): API keys come straight from the + # secrets below; max_tokens/context window come from the package's models.yaml. + - package: git+https://github.com/epoch-research/benchmarks@giles-hawkbench-newstuff + name: epoch + items: + - name: claude-fable-5 + args: + config: + reasoning_effort: "high" + max_retries: 7 + # max_sandboxes isn't user-settable; Hawk sizes it as + # 2 x sum(max_connections) across providers + max_connections: 40 + - name: gpt-5.6-sol + args: + config: + # Defaults to 'none' in GPT 5.4 + reasoning_effort: "high" + max_retries: 7 + max_connections: 40 + +# Per-sample spend cap -- the real budget. +cost_limit: 50.0 +working_limit: 43_200 # 12h + +# Prices in dollars per 1M tokens (match the epoch package's models.yaml). +# Keys must match Inspect's resolved / names. +model_cost_config: + epoch/claude-fable-5: + input: 10.0 + output: 50.0 + input_cache_read: 1.0 + input_cache_write: 12.5 + epoch/gpt-5.6-sol: + input: 5.0 + output: 30.0 + input_cache_read: 0.5 + input_cache_write: 6.25 + +secrets: + - name: ANTHROPIC_API_KEY + - name: OPENAI_API_KEY + - name: GOOGLE_API_KEY + - name: LEAN_OPEN_PROBLEMS_IMAGE_NAME + description: "The ECR repo containing the LeanOpenProblems sandbox images" + +runner: + memory: 200Gi + environment: + # TODO: Remove once default in Hawk + INSPECT_LOG_CONDENSE: "true" + ANTHROPIC_BASE_URL: https://api.anthropic.com + OPENAI_BASE_URL: https://api.openai.com/v1 + GOOGLE_BASE_URL: https://generativelanguage.googleapis.com + HAWK_RUNNER_REFRESH_CLIENT_ID: "" + HAWK_RUNNER_REFRESH_TOKEN: '' + +packages: + - inspect-ai==0.3.245