a(n) = Sum_{i=1..n} Sum_{j=1..n} Sum_{k=1..n} phi(i*j*k) / phi(j*k).

Terms

a(0) =1a(1) =11a(2) =46a(3) =139a(4) =316a(5) =633a(6) =1138a(7) =1947a(8) =3060a(9) =4583a(10) =6660a(11) =9367a(12) =12856a(13) =17153a(14) =22169a(15) =28886a(16) =36843a(17) =46179a(18) =57402a(19) =70096a(20) =84177a(21) =101268a(22) =121333a(23) =143664a(24) =168513a(25) =197084a(26) =228759a(27) =263965a(28) =304686a(29) =346832