a(n) = 32*n^6 - 48*n^4 + 18*n^2 - 1.

Terms

a(0) =-1a(1) =1a(2) =1351a(3) =19601a(4) =119071a(5) =470449a(6) =1431431a(7) =3650401a(8) =8193151a(9) =16692641a(10) =31521799a(11) =55989361a(12) =94558751a(13) =153090001a(14) =239104711a(15) =362074049a(16) =533729791a(17) =768398401a(18) =1083358151a(19) =1499219281a(20) =2040327199a(21) =2735188721a(22) =3616921351a(23) =4723725601a(24) =6099380351a(25) =7793761249