English

Solid bricks that every $b$-invariant edge is solitary

Combinatorics 2025-07-30 v1

Abstract

A graph GG is a brick if it is 3-connected and G{u,v}G-\{u,v\} has a perfect matching for any two distinct vertices uu and vv of GG. A brick GG is solid if for any two vertex disjoint odd cycles C1C_1 and C2C_2 of GG, G(V(C1)V(C2))G-(V(C_1)\cup V(C_2)) has no perfect matching. Lucchesi and Murty proposed a problem concerning the characterization of bricks, distinct from K4K_4, C6\overline{C_6} and the Petersen graph, in which every bb-invariant edge is solitary. In this paper, we show that for a solid brick GG of order nn that is distinct from K4K_4, every bb-invariant edge of GG is solitary if and only if GG is a wheel WnW_n.

Keywords

Cite

@article{arxiv.2507.21565,
  title  = {Solid bricks that every $b$-invariant edge is solitary},
  author = {Yipei Zhang and Xiumei Wang},
  journal= {arXiv preprint arXiv:2507.21565},
  year   = {2025}
}
R2 v1 2026-07-01T04:23:33.216Z