Erdős problem 22
Let and let be sufficiently large depending on . Is there a graph on vertices with at least many edges which contains no , such that the largest independent set has size at most ?
Sources
FormalConjectures/ErdosProblems/
22.lean
Retained formal statement
The matching upper bound, due to Szemerédi [Sz72]: a -free graph on vertices whose independence number is sublinear in has at most edges. That is, for every there is a such that for all sufficiently large , every -free graph on vertices with has at most edges.
∀ (ε : ℝ), 0 < ε → ∃ δ, 0 < δ ∧ ∀ᶠ (n : ℕ) in Filter.atTop, ∀ (G : SimpleGraph (Fin n)), G.CliqueFree 4 → ↑G.indepNum ≤ δ * ↑n → ↑G.edgeFinset.card ≤ (1 / 8 + ε) * ↑n ^ 2SolvedStatement only, no proof