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

Terms

a(0) =0a(1) =7a(2) =38a(3) =111a(4) =244a(5) =455a(6) =762a(7) =1183a(8) =1736a(9) =2439a(10) =3310a(11) =4367a(12) =5628a(13) =7111a(14) =8834a(15) =10815a(16) =13072a(17) =15623a(18) =18486a(19) =21679a(20) =25220a(21) =29127a(22) =33418a(23) =38111a(24) =43224a(25) =48775a(26) =54782a(27) =61263a(28) =68236a(29) =75719