a(n) = (n - 1)*(n^3 + 1) = n^4 - n^3 + n - 1, for n >= 1.

Terms

a(0) =0a(1) =9a(2) =56a(3) =195a(4) =504a(5) =1085a(6) =2064a(7) =3591a(8) =5840a(9) =9009a(10) =13320a(11) =19019a(12) =26376a(13) =35685a(14) =47264a(15) =61455a(16) =78624a(17) =99161a(18) =123480a(19) =152019a(20) =185240a(21) =223629a(22) =267696a(23) =317975a(24) =375024a(25) =439425a(26) =511784a(27) =592731a(28) =682920a(29) =783029