a(n) = 5*n^4 - 10*n^3 + 20*n^2 - 15*n + 11.

Terms

a(0) =11a(1) =61a(2) =281a(3) =911a(4) =2311a(5) =4961a(6) =9461a(7) =16531a(8) =27011a(9) =41861a(10) =62161a(11) =89111a(12) =124031a(13) =168361a(14) =223661a(15) =291611a(16) =374011a(17) =472781a(18) =589961a(19) =727711a(20) =888311a(21) =1074161a(22) =1287781a(23) =1531811a(24) =1809011a(25) =2122261a(26) =2474561a(27) =2869031a(28) =3308911a(29) =3797561