The BerlekampVanLintSeidelGraph command creates the Berlekamp-van Lint-Seidel graph.

The Berlekamp-van Lint-Seidel graph is a strongly regular graph with 243 vertices and 2673 edges.

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

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

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

$G≔\mathrm{Graph\; 1:\; an\; undirected\; graph\; with\; 243\; vertices\; and\; 2673\; edge(s)}$

$\mathrm{IsStronglyRegular}\left(G\,'\mathrm{parameters}'\right)$

$\mathrm{true},\left[22\,1\,2\right]$

"Berlekamp-van Lint-Seidel graph", Wikipedia. http://en.wikipedia.org/wiki/Berlekamp-van Lint-Seidel_graph

The GraphTheory[SpecialGraphs][BerlekampVanLintSeidelGraph] command was introduced in Maple 2020.

For more information on Maple 2020 changes, see Updates in Maple 2020.