Number of lattice paths from (0,0) to (n,n) that do not go above the diagonal x=y and consist of steps (h,v) with min(h,v) > 0 and gcd(h,v) = 1.

A308113

Number of lattice paths from (0,0) to (n,n) that do not go above the diagonal x=y and consist of steps (h,v) with min(h,v) > 0 and gcd(h,v) = 1.

Terms

    a(0) =1a(1) =1a(2) =1a(3) =2a(4) =7a(5) =22a(6) =68a(7) =205a(8) =634a(9) =2011a(10) =6490a(11) =21178a(12) =69785a(13) =231940a(14) =776794a(15) =2618951a(16) =8881373a(17) =30274185a(18) =103673227a(19) =356500914a(20) =1230497234a(21) =4261633997a(22) =14805279769a(23) =51580807121a(24) =180173390369a(25) =630864082719

External references