English

Permanent of bipartite graphs in terms of determinants

Discrete Mathematics 2025-05-19 v3

Abstract

Computing the permanent of a (0,1)(0,1)-matrix is a well-known #P\#P-complete problem. In this paper, we present an expression for the permanent of a bipartite graph in terms of the determinant of the graph and its subgraphs, obtained by successively removing rows and columns corresponding to vertices involved in vertex-disjoint 4k4k-cycles. Our formula establishes a general relationship between the permanent and the determinant for any bipartite graph. Since computing the permanent of a biadjacency matrix is equivalent to counting the number of its perfect matchings, this approach also provides a more efficient method for counting perfect matchings in certain types of bipartite graphs.

Keywords

Cite

@article{arxiv.2503.08128,
  title  = {Permanent of bipartite graphs in terms of determinants},
  author = {Surabhi Chakrabartty and Ranveer Singh},
  journal= {arXiv preprint arXiv:2503.08128},
  year   = {2025}
}

Comments

13 pages, 1 figure