a(n) = n*(4n^2 - 1)^2.

Terms

a(0) =0a(1) =9a(2) =450a(3) =3675a(4) =15876a(5) =49005a(6) =122694a(7) =266175a(8) =520200a(9) =938961a(10) =1592010a(11) =2566179a(12) =3967500a(13) =5923125a(14) =8583246a(15) =12123015a(16) =16744464a(17) =22678425a(18) =30186450a(19) =39562731a(20) =51136020a(21) =65271549a(22) =82372950a(23) =102884175a(24) =127291416a(25) =156125025a(26) =189961434a(27) =229425075a(28) =275190300a(29) =327983301