Large nearly regular induced subgraphs

dc.creatorAlon, Noga
dc.creatorKrivelevich, Michael
dc.creatorSudakov, Benny
dc.date2007-10-10
dc.date2008-02-25
dc.date.accessioned2026-07-07T09:22:42Z
dc.date.available2026-07-07T09:22:42Z
dc.descriptionFor a real c \geq 1 and an integer n, let f(n,c) denote the maximum integer f so that every graph on n vertices contains an induced subgraph on at least f vertices in which the maximum degree is at most c times the minimum degree. Thus, in particular, every graph on n vertices contains a regular induced subgraph on at least f(n,1) vertices. The problem of estimating $(n,1) was posed long time ago by Erdos, Fajtlowicz and Staton. In this note we obtain the following upper and lower bounds for the asymptotic behavior of f(n,c): (i) For fixed c>2.1, n^{1-O(1/c)} \leq f(n,c) \leq O(cn/\log n). (ii) For fixed c=1+εwith epsilon>0 sufficiently small, f(n,c) \geq n^{Ω(ε^2/ \ln (1/ε))}. (iii) Ω(\ln n) \leq f(n,1) \leq O(n^{1/2} \ln^{3/4} n). An analogous problem for not necessarily induced subgraphs is briefly considered as well.
dc.identifierhttps://arxiv.org/abs/0710.2106
dc.identifierhttp://arxiv.org/abs/0710.2106
dc.identifier.urihttp://salesiana.dossiersoluciones.com/handle/123456789/155471
dc.subjectCombinatorics
dc.titleLarge nearly regular induced subgraphs
dc.typetext

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