Helin Gong

collaborators

2 papers

math.CO2018

Proving a conjecture on chromatic polynomials by counting the number of acyclic orientations

Fengming Dong, Jun Ge, Helin Gong +3

The chromatic polynomial $P (G, x)$ of a graph $G$ of order $n$ can be expressed as $i = 1 \sum n (- 1)^{n - i} a_{i} x^{i}$ , where $a_{i}$ is interpreted as the number of broken-cycle…

math.CO2017

Several extreme coefficients of the Tutte polynomial of graphs

Helin Gong, Mengchen Li, Xian'an Jin

Let $t_{i, j}$ be the coefficient of $x^{i} y^{j}$ in the Tutte polynomial $T (G; x, y)$ of a connected bridgeless and loopless graph $G$ with order $n$ and size $m$ . It is trivial that $t_…