Number of ways to place 3 nonattacking bishops on an n X n toroidal board.

Terms

a(0) =0a(1) =0a(2) =6a(3) =128a(4) =600a(5) =2688a(6) =7350a(7) =19968a(8) =42336a(9) =89600a(10) =163350a(11) =297600a(12) =490776a(13) =809088a(14) =1242150a(15) =1906688a(16) =2774400a(17) =4036608a(18) =5633766a(19) =7862400a(20) =10613400a(21) =14326400a(22) =18818646a(23) =24718848a(24) =31740000