a(n) = n^5 - 5*n^3 + 5*n.

Terms

a(0) =1a(1) =2a(2) =123a(3) =724a(4) =2525a(5) =6726a(6) =15127a(7) =30248a(8) =55449a(9) =95050a(10) =154451a(11) =240252a(12) =360373a(13) =524174a(14) =742575a(15) =1028176a(16) =1395377a(17) =1860498a(18) =2441899a(19) =3160100a(20) =4037901a(21) =5100502a(22) =6375623a(23) =7893624a(24) =9687625a(25) =11793626a(26) =14250627a(27) =17100748a(28) =20389349a(29) =24165150