a(n) = 2*n*(9*n-1).

Terms

a(0) =16a(1) =68a(2) =156a(3) =280a(4) =440a(5) =636a(6) =868a(7) =1136a(8) =1440a(9) =1780a(10) =2156a(11) =2568a(12) =3016a(13) =3500a(14) =4020a(15) =4576a(16) =5168a(17) =5796a(18) =6460a(19) =7160a(20) =7896a(21) =8668a(22) =9476a(23) =10320a(24) =11200a(25) =12116a(26) =13068a(27) =14056a(28) =15080a(29) =16140