program fractii;
var p,k,a,b,nr,n:longint;
    f:text;
begin
    assign(f,'fractii.in');reset(f);
    read(f,n);close(f);
    nr:=1+2*(n-1);
    for p:=2 to n do
       for k:=2 to n-1 do begin
             a:=p;b:=k;
             while a<>b do
                if a>b then a:=a-b
                       else b:=b-a;
                if a=1 then nr:=nr+2;
                           end;
    assign(f,'fractii.out');rewrite(f);
    write(f,nr);close(f);
end.