program fractii;
var a,i,j,n,b,r,x:longint;
    f,g:text;
begin
assign(f,'fractii.in');
assign (g,'fractii.out');
reset (f);
rewrite (g);
read (f,n);
x:=2*n-1;
for i:=2 to n do
for j:=2 to n do
if (i mod j<>0) or (j mod i<>0) or not((i mod 2=0)and(j mod 2=0)) then
begin
a:=i;
b:=j;
repeat
r:=a mod b;
a:=b;
b:=r;
until b=0;
if a=1 then x:=x+1;
end;
write (g,x);
close (f);
close (g)
end.