a(n) = n*(120*n^4 - 480*n^3 + 762*n^2 - 556*n + 155).

Terms

a(0) =0a(1) =1a(2) =342a(3) =6315a(4) =40492a(5) =157125a(6) =456546a(7) =1099567a(8) =2321880a(9) =4448457a(10) =7907950a(11) =13247091a(12) =21145092a(13) =32428045a(14) =48083322a(15) =69273975a(16) =97353136a(17) =133878417a(18) =180626310a(19) =239606587a(20) =313076700a(21) =403556181a(22) =513841042a(23) =647018175a(24) =806479752a(25) =995937625a(26) =1219437726a(27) =1481374467