Number of cycles of length 4 in the queen graph associated with an n X n chessboard.

Terms

a(0) =0a(1) =0a(2) =3a(3) =122a(4) =776a(5) =2704a(6) =6987a(7) =15206a(8) =29224a(9) =51680a(10) =85339a(11) =134114a(12) =201792a(13) =293776a(14) =414995a(15) =572558a(16) =772656a(17) =1024320a(18) =1335123a(19) =1716234a(20) =2176728a(21) =2730128a(22) =3387131a(23) =4163830a(24) =5072664a(25) =6132512a(26) =7357675a(27) =8770034a(28) =10385872a(29) =12230288