396.lean`

Explanation legend Lean4 Domain Explanation Language (L4DEL)

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L4DEL: Lean4 Domain Explanation Language

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Credit: The upstream authors and contributors retain credit for the project and mathematics. lean4-explainer only renders their pinned source and adds the separately disclosed explanation layer.

Project sources: Pinned project documentation, Formal Conjectures paper, arXiv v1

1 declarations, 1 contain sorry, 0 declared as axioms

Erdős Problem 396

Reference: erdosproblems.com/396

Imports (1)

FormalConjecturesUtil

theorem Erdos396.erdos_396 Is it true that for every $k$ there exists $n$ such that $$\prod_{0\leq i\leq k}(n-i) \mid \binom{2n}{n}?$$ sorry line 37 source
Source documentation
Is it true that for every $k$ there exists $n$ such that $$\prod_{0\leq i\leq k}(n-i) \mid \binom{2n}{n}?$$

depends on sorry what this means
Statement uses: Iff, True, Nat, Exists, Dvd.dvd, Nat.descFactorial, HAdd.hAdd, OfNat.ofNat, Nat.centralBinom
Proof uses: sorryAx, Lean.Name, Bool.false, Lean.Name.num, Lean.Name.str, Lean.Name.anonymous
8 instances, coercions and auxiliary constants left out.

Tactic trace: 1 steps
Open to load the checked before-and-after goal states.
```
theorem erdos_396 : answer(sorry) ↔ ∀ k : ℕ, ∃ n : ℕ, descFactorial n (k + 1) ∣ centralBinom n := by
…
```