var n,k,i,j:longint;
function cmmdc(i,j:longint):boolean;
begin
 while (i<>0) and (j<>0) do
     if i>j then i:=i-j
            else j:=j-i;
 if i<=j then i:=j;
 if i=1 then cmmdc:=true
         else cmmdc:=false;
 end;
 begin
   assign(input,'fractii.in');
   reset(input);
   readln(input,n);
   close(input);
   k:=(2*n)-1;
   k:=k+(n div 2+n mod 2)-1;
   for i:=3 to n do
     for j:=2 to n do
     if cmmdc(i,j)=true then inc(k);
  assign(output,'fractii.out');
  rewrite(output);
     write(output,k);
     close(output);
     end.