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arXiv · 2312.14884

Classification of cubic tricirculant nut graphs

Ivan Damnjanović·Nino Bašić·Tomaž Pisanski·Arjana Žitnik
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Abstract

A nut graph is a simple graph whose adjacency matrix has the eigenvalue zero with multiplicity one such that its corresponding eigenvector has no zero entries. It is known that there exist no cubic circulant nut graphs. A bicirculant (resp. tricirculant) graph is defined as a graph that admits a cyclic group of automorphisms having two (resp. three) orbits of vertices of equal size. We show that there exist no cubic bicirculant nut graphs and we provide a full classification of cubic tricirculant nut graphs.

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Ivan Damnjanović, Nino Bašić, Tomaž Pisanski, Arjana Žitnik. 2023-12-22. Classification of cubic tricirculant nut graphs. https://doi.org/10.37236/12668

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