English

Uniquely Pressable Graphs: Characterization, Enumeration, and Recognition

Combinatorics 2017-06-26 v1

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

Keywords

Cite

@article{arxiv.1706.07468,
  title  = {Uniquely Pressable Graphs: Characterization, Enumeration, and Recognition},
  author = {Joshua N. Cooper and Hays W. Whitlatch},
  journal= {arXiv preprint arXiv:1706.07468},
  year   = {2017}
}

Comments

30 pages. Keywords: Pressing sequence, adjacency matrix, Cholesky factorization, binary matrix

R2 v1 2026-06-22T20:27:09.018Z