Number of ways to place 6 nonattacking kings on a 6 X n board.

Terms

a(0) =0a(1) =0a(2) =16a(3) =408a(4) =8544a(5) =62266a(6) =291908a(7) =1021254a(8) =2916232a(9) =7179314a(10) =15790572a(11) =31795390a(12) =59638832a(13) =105546666a(14) =177953044a(15) =287974838a(16) =449932632a(17) =681918370a(18) =1006409660a(19) =1450930734a(20) =2048760064a(21) =2839684634a(22) =3870800868a(23) =5197362214a(24) =6883673384