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

Terms

a(0) =0a(1) =1a(2) =11a(3) =30a(4) =58a(5) =95a(6) =141a(7) =196a(8) =260a(9) =333a(10) =415a(11) =506a(12) =606a(13) =715a(14) =833a(15) =960a(16) =1096a(17) =1241a(18) =1395a(19) =1558a(20) =1730a(21) =1911a(22) =2101a(23) =2300a(24) =2508a(25) =2725a(26) =2951a(27) =3186a(28) =3430a(29) =3683