Qianqian Liu

collaborators

3 papers

math.CO2025

Graphs with large maximum forcing number

Qianqian Liu, Ajit A. Diwan, Heping Zhang

For a graph $G$ with order $2 n$ and a perfect matching, let $f (G)$ and $F (G)$ denote the minimum and maximum forcing number of $G$ respectively. Then $0 \leq f (G) \leq F (G) \leq n - 1$ .…

math.CO2024

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 $G$ be a graph with a perfect matching $M$ . The forcing n…

math.CO2024

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…