var d,i,r,p,q,n:longint;
k:integer;
f,g:text;
begin
assign(f,'fractii.in');
reset(f);
assign(g,'fractii.out');
rewrite(g);
readln(f,n);
k:=(2*n)-1;
for p:=2 to n do
for q:=2 to n do
                         begin
                         d:=p;
                         i:=q;
                         r:=d mod i;
                         while r <> 0 do
                              begin
                              d:=i;
                              i:=r;
                              r:=d mod i;
                              end;
                         if i=1 then k:=k+1;
end;
writeln(g,k);
close(f);
close(g);
end.