The SousselierGraph command creates the Sousselier graph.

The Sousselier graph is a hypohamiltonian graph with 16 vertices and 27 edges.

$\mathrm{with}\left(\mathrm{GraphTheory}\right)\:$

$\mathrm{with}\left(\mathrm{SpecialGraphs}\right)\:$

$G≔\mathrm{SousselierGraph}\left(\right)$

$G≔\mathrm{Graph\; 1:\; an\; undirected\; graph\; with\; 16\; vertices\; and\; 27\; edges}$

$\mathrm{IsRegular}\left(G\right)$

$\mathrm{false}$

$\mathrm{ChromaticNumber}\left(G\right)$

$3$

"Sousselier graph", Wikipedia. http://en.wikipedia.org/wiki/Sousselier_graph

The GraphTheory[SpecialGraphs][SousselierGraph] command was introduced in Maple 2021.

For more information on Maple 2021 changes, see Updates in Maple 2021.