a(n) = 4n^3 + 2n^2.

Terms

a(0) =6a(1) =40a(2) =126a(3) =288a(4) =550a(5) =936a(6) =1470a(7) =2176a(8) =3078a(9) =4200a(10) =5566a(11) =7200a(12) =9126a(13) =11368a(14) =13950a(15) =16896a(16) =20230a(17) =23976a(18) =28158a(19) =32800a(20) =37926a(21) =43560a(22) =49726a(23) =56448a(24) =63750a(25) =71656a(26) =80190a(27) =89376a(28) =99238a(29) =109800