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arXiv · 1512.05944

Generation of cubic graphs and snarks with large girth

Gunnar Brinkmann·Jan Goedgebeur
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Abstract

We describe two new algorithms for the generation of all non-isomorphic cubic graphs with girth at least $k\ge 5$ which are very efficient for $5\le k \le 7$ and show how these algorithms can be efficiently restricted to generate snarks with girth at least $k$. Our implementation of these algorithms is more than 30, respectively 40 times faster than the previously fastest generator for cubic graphs with girth at least 6 and 7, respectively. Using these generators we have also generated all non-isomorphic snarks with girth at least 6 up to 38 vertices and show that there are no snarks with girth at least 7 up to 42 vertices. We present and analyse the new list of snarks with girth 6.

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Gunnar Brinkmann, Jan Goedgebeur. 2015-12-18. Generation of cubic graphs and snarks with large girth. https://doi.org/10.1002/jgt.22125

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