program fractii;

type numar=0..1000000;

var f,g:text;
    n,i,j,p,rez:numar;

function cmmdc(a,b:integer) :numar;
   begin
      if a mod b=0 then cmmdc:=b
      else
        cmmdc:=cmmdc(b,a mod b);
end;



begin
   assign(f,'fractii.in'); reset(f);
   assign(g,'fractii.out'); rewrite(g);

   read(f,n);

   rez:=2*n-2+(n div 2)+(n mod 2);

   for i:=3 to n do
      for j:=2 to n do
         begin
            if i>=j then p:=cmmdc(i,j)
            else p:=cmmdc(j,i);
            if p=1 then rez:=rez+1;
         end;

   write(g,rez);
   close(f);
   close(g);
end.