program fractie;
var f,g:text;
p,q,nr,n,s:integer;


function cmmdc(a,b:integer):boolean;
begin
while a<>b do
   if a>b then a:=a-b
           else b:=b-a;
if a=1 then cmmdc:=true
        else cmmdc:=false;
   end;
begin
assign(f,'fractii.in'); assign(g,'fractii.out');
reset(f);
rewrite(g);
read(f,n);
p:=2;
nr:=2*n-1;
while p<=n do begin
q:=1;
      while q<=n do begin
      if q<>1 then
            if cmmdc(p,q) then nr:=nr+1;
            q:=q+1;
            end;
      p:=p+1;
end;
write(g,nr);
close(f);
close(g);
readln;
end.