English

On the interlace polynomials

Combinatorics 2012-09-24 v7

Abstract

The generating function that records the sizes of directed circuit partitions of a connected 2-in, 2-out digraph D can be determined from the interlacement graph of D with respect to a directed Euler circuit; the same is true of the generating functions for other kinds of circuit partitions. The interlace polynomials of Arratia, Bollob\'as and Sorkin [J. Combin. Theory Ser. B 92 (2004) 199-233; Combinatorica 24 (2004) 567-584] extend the corresponding functions from interlacement graphs to arbitrary graphs. We introduce a multivariate interlace polynomial that is an analogous extension of a multivariate generating function for undirected circuit partitions of undirected 4-regular graphs. The multivariate polynomial incorporates several different interlace polynomials that have been studied by different authors, and its properties include invariance under a refined version of local complementation and a simple recursive definition.

Keywords

Cite

@article{arxiv.1008.0091,
  title  = {On the interlace polynomials},
  author = {Lorenzo Traldi},
  journal= {arXiv preprint arXiv:1008.0091},
  year   = {2012}
}

Comments

v7: 37 pages, 10 figures. Many corrections and improvements have been made since the first version was posted. Further changes may be made before publication in JCTB

R2 v1 2026-06-21T15:55:29.811Z