a(n) = Sum_{i=1..n} phi(i) * (ceiling(n/i) - floor(n/i)).

Terms

a(0) =0a(1) =0a(2) =1a(3) =2a(4) =5a(5) =6a(6) =11a(7) =14a(8) =19a(9) =22a(10) =31a(11) =34a(12) =45a(13) =50a(14) =57a(15) =64a(16) =79a(17) =84a(18) =101a(19) =108a(20) =119a(21) =128a(22) =149a(23) =156a(24) =175a(25) =186a(26) =203a(27) =214a(28) =241a(29) =248