a(n) = Sum_{d divides n} (-1)^(d + n/d) * d^5.

Terms

a(0) =1a(1) =-33a(2) =244a(3) =-993a(4) =3126a(5) =-8052a(6) =16808a(7) =-31713a(8) =59293a(9) =-103158a(10) =161052a(11) =-242292a(12) =371294a(13) =-554664a(14) =762744a(15) =-1014753a(16) =1419858a(17) =-1956669a(18) =2476100a(19) =-3104118a(20) =4101152a(21) =-5314716a(22) =6436344a(23) =-7737972a(24) =9768751a(25) =-12252702a(26) =14408200a(27) =-16690344a(28) =20511150