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arXiv · 1611.01010

Even and odd plane labelled bipartite trees

Yury Kochetkov
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Abstract

Let $T(n,m)$ be the set of all plane labelled bipartite trees with $n$ white vertices and $m$ black. If the number $n+m$ of vertices is even, then the set $T(n,m)$ is a union of two disjoint subsets --- subset od "even" trees and subset of "odd" trees. This partition has a clear geometric meaning.

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Yury Kochetkov. 2016-11-03. Even and odd plane labelled bipartite trees. https://arxiv.org/abs/1611.01010

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