Stella octangula numbers: a(n) = n*(2*n^2 - 1).

Terms

a(0) =0a(1) =1a(2) =14a(3) =51a(4) =124a(5) =245a(6) =426a(7) =679a(8) =1016a(9) =1449a(10) =1990a(11) =2651a(12) =3444a(13) =4381a(14) =5474a(15) =6735a(16) =8176a(17) =9809a(18) =11646a(19) =13699a(20) =15980a(21) =18501a(22) =21274a(23) =24311a(24) =27624a(25) =31225a(26) =35126a(27) =39339a(28) =43876a(29) =48749