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arXiv · 2312.05861

Banff designs: difference methods for coloring incidence graphs

Marco Buratti·Francesca Merola·Anamari Nakic·Christian Rubio-Montiel
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Abstract

We present some results on the harmonious colorings of the Levi graph of a $2$-design, focusing on Steiner $2$-designs. It is easily seen that the harmonious chromatic number of such a Levi graph is at least the number of points of the design: we study and construct Banff designs, that is, designs such that this lower bound is attained.

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Marco Buratti, Francesca Merola, Anamari Nakic, Christian Rubio-Montiel. 2024-04-23. Banff designs: difference methods for coloring incidence graphs. https://arxiv.org/abs/2312.05861

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