Number of 5-cycles in the n X n rook complement graph.

Terms

a(0) =0a(1) =0a(2) =36a(3) =3456a(4) =77040a(5) =800640a(6) =5265540a(7) =25514496a(8) =99320256a(9) =327836160a(10) =951285060a(11) =2488844160a(12) =5980596336a(13) =13384215936a(14) =28197301860a(15) =56398325760a(16) =107825391360a(17) =198142765056a(18) =351580800996a(19) =604675808640