a(n) = n*(14*n + 3).

Terms

a(0) =0a(1) =17a(2) =62a(3) =135a(4) =236a(5) =365a(6) =522a(7) =707a(8) =920a(9) =1161a(10) =1430a(11) =1727a(12) =2052a(13) =2405a(14) =2786a(15) =3195a(16) =3632a(17) =4097a(18) =4590a(19) =5111a(20) =5660a(21) =6237a(22) =6842a(23) =7475a(24) =8136a(25) =8825a(26) =9542a(27) =10287a(28) =11060a(29) =11861