a(n) = 5*n^4 - 6*n^2 + 1. Column 4 of A378066.

Terms

a(0) =1a(1) =0a(2) =57a(3) =352a(4) =1185a(5) =2976a(6) =6265a(7) =11712a(8) =20097a(9) =32320a(10) =49401a(11) =72480a(12) =102817a(13) =141792a(14) =190905a(15) =251776a(16) =326145a(17) =415872a(18) =522937a(19) =649440a(20) =797601a(21) =969760a(22) =1168377a(23) =1396032a(24) =1655425a(25) =1949376a(26) =2280825a(27) =2652832a(28) =3068577a(29) =3531360