569.lean`

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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 569

References:

erdosproblems.com/569
[EFRS93] Erdős, Paul and Faudree, R. J. and Rousseau, C. C. and Schelp, R. H., Ramsey size linear graphs. Combin. Probab. Comput. (1993), 389-399.

Imports (1)

FormalConjecturesUtil

theorem Erdos569.erdos_569 Let $k\geq 1$ sorry line 41 source
Source documentation
Let $k\geq 1$. What is the best possible $c_k$ such that $$R(C_{2k+1},H)\leq c_k m$$ for any graph $H$ on $m$ edges without isolated vertices?
This problem is #34 in Ramsey Theory in the graphs problem collection.

depends on sorry what this means
Statement uses: Nat, Real, sorryAx, Bool.false, LE.le, OfNat.ofNat, Eq, InfSet.sInf, Set.ofPred, And, LT.lt, Fintype, SimpleGraph, DecidableRel, SimpleGraph.Adj, SimpleGraph.degree, Membership.mem, Set, SimpleGraph.neighborSet, Set.ncard and 7 more
Proof uses: Lean.Name, Lean.Name.num, Lean.Name.str, Lean.Name.anonymous
38 instances, coercions and auxiliary constants left out.

Tactic trace: 1 steps
Open to load the checked before-and-after goal states.
```
theorem erdos_569 :
    let c : ℕ → ℝ := answer(sorry)
…
```
Mentions: c