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arXiv · 2411.14248

The dib-chromatic number of digraphs

Nahid Javier-Nol·Christian Rubio-Montiel·Ingrid Torres-Ramos
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Abstract

We study an extension to directed graphs of the parameter called the $b$-chromatic number of a graph in terms of acyclic vertex colorings: the dib-chromatic number. We give general bounds for this parameter. We also show some results about tournaments and regular digraphs.

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Nahid Javier-Nol, Christian Rubio-Montiel, Ingrid Torres-Ramos. 2026-03-09. The dib-chromatic number of digraphs. https://arxiv.org/abs/2411.14248

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