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FormalConjectures.ErdosProblems.«750»

Erdős Problem 750 #

References:

theorem Erdos750.erdos_750 :
True ∀ (f : NNReal), Filter.Tendsto f Filter.atTop Filter.atTop∃ (V : Type u_1) (G : SimpleGraph V), G.chromaticNumber = ∀ (m : ) (S : Set V), 0 < mS.ncard = mIS, G.IsIndepSet I m / 2 - f m I.ncard

Let $f(m)$ be some function such that $f(m)\to \infty$ as $m\to \infty$. Does there exist a graph $G$ of infinite chromatic number such that every subgraph on $m$ vertices contains an independent set of size at least $\frac{m}{2}-f(m)$?

Note that in [Er94b] the function $f$ generalises a (proven) result for $f(m) = \epsilon m$, where $\epsilon > 0$. Hence we should assume it is non-negative valued.