var f,g:text;
i,n,k,j:longint;
function cmmdc(i,j:longint):longint;
begin
repeat
if i>j then i:=i-j
       else j:=j-i;
until i=j;
cmmdc:=i;
end;
begin
assign(f,'fractii.in');
reset(f);
read(f,n);
close(f);
assign(g,'fractii.out');
rewrite(g);
k:=2*n-1;
for i := 2 to n do
for j:= 2 to n do
if (i<>j) then
if cmmdc(i,j)=1 then k:=k+1;
write(g,k);
close(g);
end.