HanoiGraph(n) returns the Hanoi graph, an undirected graph whose edges correspond to allowed moves of the tower of Hanoi problem.

The graph has $3^n$ vertices and $\frac{3}{2}{3}^n-\frac{3}{2}$ edges.

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

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

$\mathrm{H3}≔\mathrm{HanoiGraph}\left(3\right)$

$\mathrm{H3}≔\mathrm{Graph\; 1:\; an\; undirected\; graph\; with\; 27\; vertices\; and\; 39\; edges}$

The GraphTheory[SpecialGraphs][HanoiGraph] command was introduced in Maple 2025.

For more information on Maple 2025 changes, see Updates in Maple 2025.