a(n) = Sum_{k=1..n} k^3 * phi(k).

Terms

a(0) =1a(1) =9a(2) =63a(3) =191a(4) =691a(5) =1123a(6) =3181a(7) =5229a(8) =9603a(9) =13603a(10) =26913a(11) =33825a(12) =60189a(13) =76653a(14) =103653a(15) =136421a(16) =215029a(17) =250021a(18) =373483a(19) =437483a(20) =548615a(21) =655095a(22) =922769a(23) =1033361a(24) =1345861a(25) =1556773a(26) =1911067a(27) =2174491a(28) =2857383a(29) =3073383