Number of ways to place a non-attacking white and black king on n X n chessboard.

Terms

a(0) =0a(1) =0a(2) =32a(3) =156a(4) =456a(5) =1040a(6) =2040a(7) =3612a(8) =5936a(9) =9216a(10) =13680a(11) =19580a(12) =27192a(13) =36816a(14) =48776a(15) =63420a(16) =81120a(17) =102272a(18) =127296a(19) =156636a(20) =190760a(21) =230160a(22) =275352a(23) =326876a(24) =385296a(25) =451200a(26) =525200a(27) =607932a(28) =700056a(29) =802256