Icosahedral numbers: a(n) = n*(5*n^2 - 5*n + 2)/2.

Terms

a(0) =1a(1) =12a(2) =48a(3) =124a(4) =255a(5) =456a(6) =742a(7) =1128a(8) =1629a(9) =2260a(10) =3036a(11) =3972a(12) =5083a(13) =6384a(14) =7890a(15) =9616a(16) =11577a(17) =13788a(18) =16264a(19) =19020a(20) =22071a(21) =25432a(22) =29118a(23) =33144a(24) =37525a(25) =42276a(26) =47412a(27) =52948a(28) =58899a(29) =65280