program fractii;
var n,k,i,j:longint;f1,f2:text;

function ireduct(a,b:integer):boolean;
var r:longint;
begin
repeat
	r:=a mod b;
	a:=b;
	b:=r;
until r=0;
if a=1 then ireduct:=true
	else ireduct:=false;
end;

begin
assign(f1,'fractii.in');
reset(f1);
read(f1,n);
close(f1);
if n=0 then k:=0 else
k:=2*n-1;
for i:=2 to n do
	for j:=2 to n do
  	if ireduct(i,j) then k:=k+1;
assign(f2,'fractii.out') ;
rewrite(f2);
write(f2,k);
close(f2);
end.