The n-th n-gonal number: a(n) = n*(n^2 - 3*n + 4)/2.

Terms

a(0) =0a(1) =1a(2) =2a(3) =6a(4) =16a(5) =35a(6) =66a(7) =112a(8) =176a(9) =261a(10) =370a(11) =506a(12) =672a(13) =871a(14) =1106a(15) =1380a(16) =1696a(17) =2057a(18) =2466a(19) =2926a(20) =3440a(21) =4011a(22) =4642a(23) =5336a(24) =6096a(25) =6925a(26) =7826a(27) =8802a(28) =9856a(29) =10991