Minimum forcing numbers of perfect matchings of circular and prismatic graphs
Fuente:
arXiv
Enregistré dans:
| Auteurs principaux: | , |
|---|---|
| Format: | Preprint |
| Publié: |
2025
|
| Sujets: | |
| Accès en ligne: | |
| Tags: |
Ajouter un tag
Pas de tags, Soyez le premier à ajouter un tag!
|
| _version_ | 1866913692381085696 |
|---|---|
| author | Shi, Qiaoyun Zhang, Heping |
| author_facet | Shi, Qiaoyun Zhang, Heping |
| contents | Let $G$ be a graph with a perfect matching. Denote by $f(G)$ the minimum size of a matching in $G$ which is uniquely extendable to a perfect matching in $G$. Diwan (2019) proved by linear algebra that for $d$-hypercube $Q_d$ ($d\geq 2)$, $f(Q_n)=2^{d-2}$, settling a conjecture proposed by Pachter and Kim in 1998. Recently Mohammadian generalized this method to obtain a general result: for a bipartite graph $G$ on $n$ vertices, if there exists an involutory matrix $A$ on a field $F$ as a weighted adjacency matrix then $f(G\Box K_2)=\frac{n}{2}$. In this paper, under the same condition we obtain $f(G\Box C_{2k})=n ~(k\ge2)$. Also this method can be applied to some non-balanced bipartite graphs $G$ whenever $G$ admit a weighted bi-adjacency matrix with orthogonal rows. |
| format | Preprint |
| id |
arxiv_https___arxiv_org_abs_2502_10981 |
| institution | arXiv |
| publishDate | 2025 |
| record_format | arxiv |
| spellingShingle | Minimum forcing numbers of perfect matchings of circular and prismatic graphs Shi, Qiaoyun Zhang, Heping Combinatorics 05C70 05C50 Let $G$ be a graph with a perfect matching. Denote by $f(G)$ the minimum size of a matching in $G$ which is uniquely extendable to a perfect matching in $G$. Diwan (2019) proved by linear algebra that for $d$-hypercube $Q_d$ ($d\geq 2)$, $f(Q_n)=2^{d-2}$, settling a conjecture proposed by Pachter and Kim in 1998. Recently Mohammadian generalized this method to obtain a general result: for a bipartite graph $G$ on $n$ vertices, if there exists an involutory matrix $A$ on a field $F$ as a weighted adjacency matrix then $f(G\Box K_2)=\frac{n}{2}$. In this paper, under the same condition we obtain $f(G\Box C_{2k})=n ~(k\ge2)$. Also this method can be applied to some non-balanced bipartite graphs $G$ whenever $G$ admit a weighted bi-adjacency matrix with orthogonal rows. |
| title | Minimum forcing numbers of perfect matchings of circular and prismatic graphs |
| topic | Combinatorics 05C70 05C50 |
| url | https://arxiv.org/abs/2502.10981 |