%I #5 May 14 2019 11:00:59

%S 0,12,22928,10221735256,1881495851872220832

%N Number of (undirected) Hamiltonian paths on the n X n queen graph.

%H Eric Weisstein's World of Mathematics, <a href="http://mathworld.wolfram.com/HamiltonianPath.html">Hamiltonian Path</a>

%H Eric Weisstein's World of Mathematics, <a href="http://mathworld.wolfram.com/QueenGraph.html">Queen Graph</a>

%F a(n) = A158664(n)/2.

%Y Cf. A158664.

%K nonn,more,hard

%O 1,2

%A _Eric W. Weisstein_, May 14 2019