English

Several extreme coefficients of the Tutte polynomial of graphs

Combinatorics 2017-05-30 v1

Abstract

Let ti,jt_{i,j} be the coefficient of xiyjx^iy^j in the Tutte polynomial T(G;x,y)T(G;x,y) of a connected bridgeless and loopless graph GG with order nn and size mm. It is trivial that t0,mn+1=1t_{0,m-n+1}=1 and tn1,0=1t_{n-1,0}=1. In this paper, we obtain expressions of another eight extreme coefficients ti,jt_{i,j}'s with (i,j)=(0,mn)(i,j)=(0,m-n),(0,mn1)(0,m-n-1),(n2,0)(n-2,0),(n3,0)(n-3,0),(1,mn)(1,m-n),(1,mn1)(1,m-n-1),(n2,1)(n-2,1) and (n3,1)(n-3,1) in terms of small substructures of GG. Among them, the former four can be obtained by using coefficients of the highest, second highest and third highest terms of chromatic or flow polynomials, and vice versa. We also discuss their duality property and their specializations to extreme coefficients of the Jones polynomial.

Keywords

Cite

@article{arxiv.1705.10023,
  title  = {Several extreme coefficients of the Tutte polynomial of graphs},
  author = {Helin Gong and Mengchen Li and Xian'an Jin},
  journal= {arXiv preprint arXiv:1705.10023},
  year   = {2017}
}

Comments

20 pages, 3 figures