For 1<=x<=n, 1<=y<=n, write gcd(x,y) = u*x+v*y with u,v minimal; a(n) = sum of the values of |u|.

Terms

a(0) =0a(1) =1a(2) =4a(3) =8a(4) =17a(5) =24a(6) =42a(7) =58a(8) =82a(9) =104a(10) =149a(11) =177a(12) =240a(13) =286a(14) =340a(15) =404a(16) =512a(17) =579a(18) =714a(19) =799a(20) =910a(21) =1031a(22) =1229a(23) =1341a(24) =1539a(25) =1711a(26) =1918a(27) =2093a(28) =2408a(29) =2574