1 citations · 2 across the 5 of their papers we have counts for
6 papers
Graphs with large maximum forcing number
Qianqian Liu, Ajit A. Diwan, Heping Zhang
For a graph with order and a perfect matching, let and denote the minimum and maximum forcing number of respectively. Then .…
The maximum forcing numbers of quadriculated tori
Qianqian Liu, Yaxian Zhang, Heping Zhang
Klein and Randic (1985) proposed the concept of forcing number, which has an application in chemical resonance theory. Let be a graph with a perfect matching . The forcing n…
Components of domino tilings under flips in quadriculated tori
Qianqian Liu, Yaxian Zhang, Heping Zhang
In a region R consisting of unit squares, a (domino) tiling is a collection of dominoes (the union of two adjacent squares) which pave fully the region. The flip graph of R is defi…
Components of domino tilings under flips in quadriculated cylinder and torus
Qianqian Liu, Jingfeng Wang, Chunmei Li +1
In a region consisting of unit squares, a domino is the union of two adjacent squares and a (domino) tiling is a collection of dominoes with disjoint interior whose union is th…
Weighted Dyck paths with special restrictions on the levels of valleys
Yidong Sun, Qianqian Liu, Yanxin Liu
This paper concentrates on the set of weighted Dyck paths of length with special restrictions on the level of valleys. We first give its explicit formula of th…
Some tight bounds on the minimum and maximum forcing numbers of graphs
Qianqian Liu, Heping Zhang
Let be a simple graph with vertices and a perfect matching. We denote by and the minimum and maximum forcing number of , respectively. Hetyei obtained tha…