a(n) = floor(n^2/3 + n^3/2).

Terms

a(0) =0a(1) =0a(2) =5a(3) =16a(4) =37a(5) =70a(6) =120a(7) =187a(8) =277a(9) =391a(10) =533a(11) =705a(12) =912a(13) =1154a(14) =1437a(15) =1762a(16) =2133a(17) =2552a(18) =3024a(19) =3549a(20) =4133a(21) =4777a(22) =5485a(23) =6259a(24) =7104a(25) =8020a(26) =9013a(27) =10084a(28) =11237a(29) =12474