ON A СOMBINATORIAL APPLICATION OF ULTRAFILTER THEORY: A NEW CONSTRUCTION OF TRIANGLE-FREE GRAPHS WITH ARBITRARILY LARGE CHROMATIC NUMBER

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Resumo

The paper describes a new method for constructing triangle-free graphs with an arbitrarily large chromatic number. The method is substantiated using properties of various types of ultrafilter extensions of functions and predicates.

Sobre autores

N. Polyakov

HSE University

Email: npolyakov@hse.ru
Moscow, Russia

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