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arXiv · 2512.20089

Spectral radius and size conditions for fractional $(a,b,m)$-covered graphs

Zengzhao Xu·Ligong Wang·Weige Xi
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Abstract

A fractional $(a,b,m)$-covered graph is a generalization of the concept of a fractional $[a,b]$-covered graph. For any $H \subseteq G$ with edge set $|E(H)| = m$, if there exists a fractional $[a,b]$-factor (the corresponding fractional indicator function is $h$) such that $h(e) = 1$ for any $e \in H$, then the graph $G$ is called a fractional $(a,b,m)$-covered graph. In this paper, we characterize the conditions for a graph to be a fractional $(a,b,m)$-covered graph from the perspectives of spectral radius and size, respectively.

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Zengzhao Xu, Ligong Wang, Weige Xi. 2025-12-23. Spectral radius and size conditions for fractional $(a,b,m)$-covered graphs. https://arxiv.org/abs/2512.20089

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