program fractii;
   var  n,p,q,i,a:longint;f,g:text;
   begin
   assign(f,'fractii.in');reset(f);
   assign(g,'fractii.out');rewrite(g);
   readln(f,n);
   for p:=1 to n do begin
   if q<n then begin
   q:=q+1;
   if i<n mod 2 then begin
   i:=i+1;
   if (p mod i=0)and(q mod i=0)then inc(a);end;
   if a=0 then write(g,p,'/',q,' ');
   a:=0;
   end;
   end;
   close(f);
   close(g);
   end.