Spectral radius and rainbow $k$-factors in a bipartite graph family

Meng Chen; Ruifang Liu

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arXiv · 2603.18517

Spectral radius and rainbow $k$-factors in a bipartite graph family

Meng Chen·Ruifang Liu

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Abstract

Let $\mathcal{G}=\{G_1, G_2, \ldots , G_{kn}\}$ be a family of balanced bipartite graphs on the same vertex set $[2n]$. A rainbow $k$-factor of $\mathcal{G}$ is defined as a $k$-factor such that any two distinct edges come from different graphs in $\mathcal{G}.$ In this paper, we provide a tight sufficient condition in terms of the spectral radius for a family of balanced bipartite graphs $\mathcal{G}$ to contain a rainbow $k$-factor. Furthermore, we completely characterize the corresponding spectral extremal graph.

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Meng Chen, Ruifang Liu. 2026-03-19. Spectral radius and rainbow $k$-factors in a bipartite graph family. https://arxiv.org/abs/2603.18517

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