Results 31 to 40 of about 1,180 (130)
A Ramsey theorem for pairs in trees [PDF]
Fundamenta Mathematicae, 2019 We prove a sharp structural result concerning finite colorings of pairs in well-founded trees.
Ryan M. Causey, Cade Doebele
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Superfilters, Ramsey theory, and van der Waerden's Theorem [PDF]
, 2009 Superfilters are generalized ultrafilters, which capture the underlying concept in Ramsey theoretic theorems such as van der Waerden's Theorem. We establish several properties of superfilters, which generalize both Ramsey's Theorem and its variant for ...
Banakh +27 more
core +2 more sources
On uniform relationships between combinatorial problems [PDF]
, 2015 The enterprise of comparing mathematical theorems according to their logical strength is an active area in mathematical logic, with one of the most common frameworks for doing so being reverse mathematics. In this setting, one investigates which theorems
Dorias, FG +4 more
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Phase transitions related to the pigeonhole principle [PDF]
, 2014 Since Paris introduced them in the late seventies (Paris1978), densities turned out to be useful for studying independence results. Motivated by their simplicity and surprising strength we investigate the combinatorial complexity of two such densities ...
A. Weiermann +4 more
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A sharp threshold for van der Waerden's theorem in random subsets
Discrete Analysis, 2016 A sharp threshold for van der Waerden's theorem in random subsets, Discrete Analysis, 2016:7, 19 pp. In recent years there has been a great deal of progress on problems that arise when one takes a notable combinatorial theorem such as Ramsey's theorem ...
Ehud Friedgut +3 more
doaj +1 more source
Electronic Notes in Discrete Mathematics, 2007 We present a unified approach to proving Ramsey-type theorems for graphs with a forbidden induced subgraph which can be used to extend and improve the earlier results of Rodl, Erdos-Hajnal, Promel-Rodl, Nikiforov, Chung-Graham, and Luczak-Rodl. The proofs are based on a simple lemma (generalizing one by Graham, Rodl, and Rucinski) that can be used as a
Jacob Fox, Benny Sudakov
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A Ramsey-Type Theorem in the Plane [PDF]
Combinatorics, Probability and Computing, 1994 We show that, for any finite set P of points in the plane and for any integer k ≥ 2, there is a finite set R = R(P, k) with the following property: for any k-colouring of R there is a monochromatic set , ⊆ R, such that is combinatorially equivalent to the set P, and the convex hull of P contains no point of R \ .
Nešetřil, Jaroslav, Valtr, Pavel
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Journal of Graph Theory, EarlyView.ABSTRACT An inversion of a tournament T $T$ is obtained by reversing the direction of all edges with both endpoints in some set of vertices. Let inv k ( T ) ${\text{inv}}_{k}(T)$ be the minimum length of a sequence of inversions using sets of size at most k $k$ that result in the transitive tournament.
Raphael Yuster
wiley +1 more source
Easton's theorem for Ramsey and strongly Ramsey cardinals
Annals of Pure and Applied Logic, 2015 We show that, assuming GCH, if $ $ is a Ramsey or a strongly Ramsey cardinal and $F$ is a class function on the regular cardinals having a closure point at $ $ and obeying the constraints of Easton's theorem, namely, $F( )\leq F( )$ for $ \leq $ and $
Victoria Gitman, Brent Cody
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Agricultural Economics, EarlyView.ABSTRACT The Biden Administration significantly raised its Social Cost of Carbon because of revised predictions that increased global crop yield losses under a changing climate. Although previous studies have estimated and predicted the impact of climate on crop yield distributions—highlighting differences in conditional moments or distributions (given
Hanjun Lu, Alan P. Ker
wiley +1 more source