a(n) = (n+1)^3*(2n+1)(5n+1).

Terms

a(0) =1a(1) =144a(2) =1485a(3) =7168a(4) =23625a(5) =61776a(6) =138229a(7) =276480a(8) =508113a(9) =874000a(10) =1425501a(11) =2225664a(12) =3350425a(13) =4889808a(14) =6949125a(15) =9650176a(16) =13132449a(17) =17554320a(18) =23094253a(19) =29952000a(20) =38349801a(21) =48533584a(22) =60774165a(23) =75368448a(24) =92640625a(25) =112943376