a(n) = n^3 - n^2 - n - 1.

Terms

a(0) =-1a(1) =-2a(2) =1a(3) =14a(4) =43a(5) =94a(6) =173a(7) =286a(8) =439a(9) =638a(10) =889a(11) =1198a(12) =1571a(13) =2014a(14) =2533a(15) =3134a(16) =3823a(17) =4606a(18) =5489a(19) =6478a(20) =7579a(21) =8798a(22) =10141a(23) =11614a(24) =13223a(25) =14974a(26) =16873a(27) =18926a(28) =21139a(29) =23518