FormalConjectures/ErdosProblems/997.lean
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- Lean4 Domain Explanation Language
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Project sources: Pinned project documentation, Formal Conjectures paper, arXiv v1
4 declarations, 3 contain sorry, 0 declared as axioms
Erdős Problem 997
References:
- erdosproblems.com/997
- [APSSV26] B. Alexeev, M. Putterman, M. Sawhney, M. Sellke, and G. Valiant, Short proofs in combinatorics and number theory. arXiv:2603.29961 (2026).
- [CLLW24] J. Champagne, T. Le, Y.-R. Liu, and T. D. Wooley, Well-distribution modulo one and the primes. arXiv:2406.19491 (2024).
- [Er64b] Erdős, P., Problems and results on diophantine approximations. Compositio Math. (1964), 52-65.
- [Er85e] Erdős, P., Some problems and results in number theory. Number theory and combinatorics. Japan 1984 (Tokyo, Okayama and Kyoto, 1984) (1985), 65-87.
- [Hl55] Hlawka, Edmund, Zur formalen {T}heorie der {G}leichverteilung in kompakten {G}ruppen. Rend. Circ. Mat. Palermo (2) (1955), 33--47.
- [Mo26] P. Monticone, Lean formalisation of Erdős problem 997 (2026)
Imports (1)
- def
Erdos997.IsWellDistributedCall line 52 sourceSource documentation
Call $x_1,x_2,\ldots \in (0,1)$ well-distributed if, for every $\epsilon>0$, if $k$ is sufficiently large then, for all $n>0$ and intervals $I\subseteq [0,1]$, $\lvert \# \{ n < m\leq n+k : x_m\in I\} - \lvert I\rvert k\rvert < \epsilon k.$
The notion of a well-distributed sequence was introduced by Hlawka and Petersen [Hl55].
standard axioms: Classical.choice, Quot.sound, propext what this means
Statement uses:
Nat,RealProof uses:
GT.gt,OfNat.ofNat,Filter.Eventually,LE.le,Finset,Finset.filter,Membership.mem,Set,Set.Ico,Finset.Ioc,HAdd.hAdd,LT.lt,abs,HSub.hSub,Finset.card,HMul.hMul,Filter.atTop23 instances, coercions and auxiliary constants left out.
def IsWellDistributed (x : ℕ → ℝ) : Prop := …
- theorem
Erdos997.erdos_997sorry line 67 sourcedepends on sorry what this means
Statement uses:
Iff,True,Real,Not, Erdos997.IsWellDistributed,Nat,Int.fract,HMul.hMul,Nat.nth,Nat.PrimeProof uses:
sorryAx,Lean.Name,Bool.false,Lean.Name.num,Lean.Name.str,Lean.Name.anonymous,OfNat.ofNat15 instances, coercions and auxiliary constants left out.
Tactic trace: 1 steps
Open to load the checked before-and-after goal states.
- theorem
Erdos997.erdos_997.variants.lacunaryErdős proved that, if $n_k$ is a lacunary sequence, then the sequence $\{ \alpha n_k\}$ is not well-distributed for almost all $\alpha$ sorry line 77 sourceSource documentation
Erdős proved that, if $n_k$ is a lacunary sequence, then the sequence $\{ \alpha n_k\}$ is not well-distributed for almost all $\alpha$.
depends on sorry what this means
Statement uses:
Nat, IsLacunary,Filter.Eventually,Real,Not, Erdos997.IsWellDistributed,Int.fract,HMul.hMul,MeasureTheory.ae,MeasureTheory.Measure,MeasureTheory.MeasureSpace.volumeProof uses:
sorryAx,Lean.Name,Bool.false,Lean.Name.num,Lean.Name.str,Lean.Name.anonymous,OfNat.ofNat23 instances, coercions and auxiliary constants left out.
Tactic trace: 1 steps
Open to load the checked before-and-after goal states.
theorem erdos_997.variants.lacunary (n : ℕ → ℕ) (h : IsLacunary n) : ∀ᵐ α, ¬ IsWellDistributed (fun k ↦ Int.fract (α * (n k : ℝ))) := by …Mentions: IsLacunary, Erdos997.IsWellDistributed
- theorem
Erdos997.erdos_997.variants.irrationalHe also claimed in [Er64b] to have proved that there exists an irrational $\alpha$ for which $\{\alpha p_n\}$ is not well-distributed sorry line 90 sourceSource documentation
He also claimed in [Er64b] to have proved that there exists an irrational $\alpha$ for which $\{\alpha p_n\}$ is not well-distributed. He later retracted this claim in [Er85e], saying "The theorem is no doubt correct and perhaps will not be difficult to prove but I never was able to reconstruct my 'proof' which perhaps never existed."
The existence of such an $\alpha$ was established by Champagne, Le, Liu, and Wooley [CLLW24].
depends on sorry what this means
Statement uses:
Exists,Real,And,Irrational,Not, Erdos997.IsWellDistributed,Nat,Int.fract,HMul.hMul,Nat.nth,Nat.PrimeProof uses:
sorryAx,Lean.Name,Bool.false,Lean.Name.num,Lean.Name.str,Lean.Name.anonymous,OfNat.ofNat15 instances, coercions and auxiliary constants left out.
Tactic trace: 1 steps
Open to load the checked before-and-after goal states.
theorem erdos_997.variants.irrational : ∃ α : ℝ, Irrational α ∧ ¬ IsWellDistributed (fun n ↦ Int.fract (α * (n.nth Nat.Prime))) := by …Mentions: Erdos997.IsWellDistributed