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arXiv · 1706.07468

Uniquely Pressable Graphs: Characterization, Enumeration, and Recognition

Joshua N. Cooper·Hays W. Whitlatch
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Abstract

We consider "pressing sequences", a certain kind of transformation of graphs with loops into empty graphs, motivated by an application in phylogenetics. In particular, we address the question of when a graph has precisely one such pressing sequence, thus answering an question from Cooper and Davis (2015). We characterize uniquely pressable graphs, count the number of them on a given number of vertices, and provide a polynomial time recognition algorithm. We conclude with a few open questions. Keywords: Pressing sequence, adjacency matrix, Cholesky factorization, binary matrix

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Joshua N. Cooper, Hays W. Whitlatch. 2017-06-22. Uniquely Pressable Graphs: Characterization, Enumeration, and Recognition. https://arxiv.org/abs/1706.07468

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