a(n) = (p^3 - p^2)/2, where p = prime(n).

Terms

a(0) =2a(1) =9a(2) =50a(3) =147a(4) =605a(5) =1014a(6) =2312a(7) =3249a(8) =5819a(9) =11774a(10) =14415a(11) =24642a(12) =33620a(13) =38829a(14) =50807a(15) =73034a(16) =100949a(17) =111630a(18) =148137a(19) =176435a(20) =191844a(21) =243399a(22) =282449a(23) =348524a(24) =451632a(25) =510050a(26) =541059a(27) =606797a(28) =641574a(29) =715064