Pattern avoiding permutations and independent sets in graphs

Christian Bean; Murray Tannock; Henning Ulfarsson

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arXiv · 1512.08155

Pattern avoiding permutations and independent sets in graphs

Christian Bean·Murray Tannock·Henning Ulfarsson

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Abstract

We introduce a new method for encoding permutations as weighted independent sets in a family of graphs we call cores. The encoding allows us to enumerate (1324, 2143)-, (1234, 1324, 2143)-, (1234, 1324, 1432, 3214)-avoiding permutations with respect to their number of "boundary points" and the size of the independent set in the graph they correspond to.

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Christian Bean, Murray Tannock, Henning Ulfarsson. 2019-12-12. Pattern avoiding permutations and independent sets in graphs. https://arxiv.org/abs/1512.08155

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