var f,g : text;
    n,i,j,total : longint;

function verifica(x,y : longint) : boolean;

begin
    while x <> y do
        if x > y then x := x-y
        else y := y-x;

    if y = 1 then verifica := true
    else verifica := false;
end;

begin
    assign(f,'fractii.in'); reset(f);
    assign(g,'fractii.out'); rewrite(g);
    read(f,n);
    total := 2*n-1;
    for i := 2 to n-1 do
        for j := i+1 to n do
            if verifica(i,j) then total := total+2;
    write(g,total);

    close(f); close(g);
end.