var f,g:text;
    n,a,b,i,j,r,k:longint;
begin
assign(f,'fractii.in');reset(f);
assign(g,'fractii.out');rewrite(g);
readln(f,n);
for i:=1 to n do begin
    a:=i;
    for j:=1 to n do begin
        b:=j;
        while b<>0 do begin
              r:=a mod b;
              a:=b;
              b:=a;
        end;
        if a=1 then k:=k+1;
    end;
end;
write(g,k);
close(g);
end.