Second 11-gonal (or hendecagonal) numbers: a(n) = n*(9*n+7)/2.

Terms

a(0) =0a(1) =8a(2) =25a(3) =51a(4) =86a(5) =130a(6) =183a(7) =245a(8) =316a(9) =396a(10) =485a(11) =583a(12) =690a(13) =806a(14) =931a(15) =1065a(16) =1208a(17) =1360a(18) =1521a(19) =1691a(20) =1870a(21) =2058a(22) =2255a(23) =2461a(24) =2676a(25) =2900a(26) =3133a(27) =3375a(28) =3626a(29) =3886