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%I #16 Jun 20 2017 23:07:43
%S 0,1,312,3228524,6198979538330,3366323909717796339009
%N Number of (undirected) cycles in the n X n rook graph.
%H Eric Weisstein's World of Mathematics, <a href="http://mathworld.wolfram.com/GraphCycle.html">Graph Cycle</a>
%H Eric Weisstein's World of Mathematics, <a href="http://mathworld.wolfram.com/RookGraph.html">Rook Graph</a>
%Y Main diagonal of A286418.
%Y Cf. A269561, A096970.
%K nonn,more
%O 1,3
%A _Eric W. Weisstein_, Dec 28 2013
%E a(6) from _Andrew Howroyd_, May 08 2017