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On Free Semigroups and Ramsey Numbers

Published online by Cambridge University Press:  20 November 2018

Gerard Lallement*
Affiliation:
Pennsylvania State University, Pennsylvania16802
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Abstract

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If the length of a word w in a free semigroup F(X) satisfies , then for every partition of F(X) into k classes, w has n consecutive factors of length ≥p in the same class. As a consequence, the diagonal Ramsey numbers R(pn+1, p+1, k) have 1+pnk as lower bound.

Type
Research Article
Copyright
Copyright © Canadian Mathematical Society 1974

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