a(n) = n^2 - n^3 + n^4.

Terms

a(0) =0a(1) =1a(2) =12a(3) =63a(4) =208a(5) =525a(6) =1116a(7) =2107a(8) =3648a(9) =5913a(10) =9100a(11) =13431a(12) =19152a(13) =26533a(14) =35868a(15) =47475a(16) =61696a(17) =78897a(18) =99468a(19) =123823a(20) =152400a(21) =185661a(22) =224092a(23) =268203a(24) =318528a(25) =375625a(26) =440076a(27) =512487a(28) =593488a(29) =683733