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

Terms

a(0) =0a(1) =6a(2) =34a(3) =102a(4) =228a(5) =430a(6) =726a(7) =1134a(8) =1672a(9) =2358a(10) =3210a(11) =4246a(12) =5484a(13) =6942a(14) =8638a(15) =10590a(16) =12816a(17) =15334a(18) =18162a(19) =21318a(20) =24820a(21) =28686a(22) =32934a(23) =37582a(24) =42648a(25) =48150a(26) =54106a(27) =60534a(28) =67452a(29) =74878