64.lean`

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L4DEL: Lean4 Domain Explanation Language

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

1 declarations, 1 contain sorry, 0 declared as axioms

Erdős Problem 64

Reference: erdosproblems.com/64

Imports (1)

FormalConjecturesUtil

theorem Erdos64.erdos_64 Does every finite graph with minimum degree at least $3$ contain a cycle of length $2^k$ for some $k \geq 2$? sorry line 35 source
Source documentation
Does every finite graph with minimum degree at least $3$ contain a cycle of length $2^k$ for some $k \geq 2$?

depends on sorry what this means
Statement uses: Iff, True, SimpleGraph, Fintype, DecidableRel, SimpleGraph.Adj, GE.ge, Nat, SimpleGraph.minDegree, OfNat.ofNat, Exists, SimpleGraph.Walk, And, SimpleGraph.Walk.IsCycle, Eq, SimpleGraph.Walk.length, HPow.hPow
Proof uses: sorryAx, Lean.Name, Bool.false, Lean.Name.num, Lean.Name.str, Lean.Name.anonymous
12 instances, coercions and auxiliary constants left out.

Tactic trace: 1 steps
Open to load the checked before-and-after goal states.
```
theorem erdos_64 :
    answer(sorry) ↔ ∀ (V : Type*) (G : SimpleGraph V) [Fintype V] [DecidableRel G.Adj],
        G.minDegree ≥ 3 → ∃ (k : ℕ) (v : V) (c : G.Walk v v),
            k ≥ 2 ∧ c.IsCycle ∧ c.length = 2^k := by
…
```
Mentions: c