Number of inequivalent (mod D_8) ways to place 3 nonattacking knights on an n X n board.

Terms

a(0) =1a(1) =9a(2) =40a(3) =195a(4) =618a(5) =1751a(6) =4075a(7) =8794a(8) =17015a(9) =31268a(10) =53666a(11) =88781a(12) =140200a(13) =215405a(14) =320013a(15) =465436a(16) =659965a(17) =920114a(18) =1257580a(19) =1695303a(20) =2249206a(21) =2950131a(22) =3819135a(23) =4896590a(24) =6209683a(25) =7810096a(26) =9732230a(27) =12041009a(28) =14779220a(29) =18027113