The DoyleGraph() command returns the Doyle graph, also known as the Holt graph, an undirected graph with 27 vertices and 54 edges.

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

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

$G≔\mathrm{DoyleGraph}\left(\right)$

$G≔\mathrm{Graph\; 1:\; an\; undirected\; graph\; with\; 27\; vertices\; and\; 54\; edge(s)}$

$\mathrm{GroupTheory}:-\mathrm{GroupOrder}\left(\mathrm{AutomorphismGroup}\left(G\right)\right)$

$54$

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

"Doyle graph", Wikipedia. http://en.wikipedia.org/wiki/Doyle_graph

The GraphTheory[SpecialGraphs][DoyleGraph] command was introduced in Maple 2018.

For more information on Maple 2018 changes, see Updates in Maple 2018.