Convolution of sigma(n) with phi(n).

Terms

a(0) =1a(1) =4a(2) =9a(3) =19a(4) =31a(5) =54a(6) =74a(7) =117a(8) =148a(9) =217a(10) =252a(11) =366a(12) =408a(13) =562a(14) =612a(15) =833a(16) =853a(17) =1171a(18) =1203a(19) =1566a(20) =1606a(21) =2104a(22) =2030a(23) =2718a(24) =2655a(25) =3347a(26) =3332a(27) =4262a(28) =3954a(29) =5226