var n,cnt,i,j,x,p,q:longint;
    ok:boolean;
    f,g:text;
begin
assign(f,'fractii.in');
assign(g,'fractii.out');
reset (f);
rewrite (g);
read (f,n);
cnt:=n;
x:=2;
ok:=false;
while x<=n do
      begin
       for i:=1 to n do
           begin
            p:=i;
            q:=x;
            while p<>q do
                  if p>q then p:=p-q
                  else
                  q:=q-p;
            if q=1 then cnt:=cnt+1;
           end;
       x:=x+1;
      end;
write (g,(cnt));
close (f);
close (g);
end.