19-gonal (or enneadecagonal) numbers: n(17n-15)/2.

Terms

a(0) =0a(1) =1a(2) =19a(3) =54a(4) =106a(5) =175a(6) =261a(7) =364a(8) =484a(9) =621a(10) =775a(11) =946a(12) =1134a(13) =1339a(14) =1561a(15) =1800a(16) =2056a(17) =2329a(18) =2619a(19) =2926a(20) =3250a(21) =3591a(22) =3949a(23) =4324a(24) =4716a(25) =5125a(26) =5551a(27) =5994a(28) =6454a(29) =6931