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arXiv · 2610.13458

The DP color function of joins and vertex-gluing of hypergraphs

Ruiyi Cui·Liangxia Wan·Fengming Dong
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Abstract

The DP color function $P_{DP}(\mathcal{H}, k)$ of a hypergraph $\mathcal{H}$ is defined as the minimum possible value of $P_{DP}(\mathcal{H}, \mathcal{F})$ taken over all $k$-fold covers $\mathcal{F}$ of $\mathcal{H}$. It serves as an extension of the classical chromatic polynomial. In this paper, we investigate the DP color function for two constructions: the join of a hypergraph with a complete graph and vertex-gluings of certain hypergraphs. Both constructions extend some results of Becker et al.

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Ruiyi Cui, Liangxia Wan, Fengming Dong. 2026-10-09. The DP color function of joins and vertex-gluing of hypergraphs. https://arxiv.org/abs/2610.13458

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