program p1;
var f:text;
    n,d,i,j,e,g,r:longint;
begin
assign(f,'fractii.in');reset(f);
read(f,n);
close(f);
d:=0;
for i:=1 to n-1 do
    for j:=i+1 to n do
        begin
        e:=i;
        g:=j;
        r:=e mod g;
        while r<>0 do
              begin
              e:=g;
              g:=r;
              r:=e mod g;
              end;
        if g=1 then d:=d+1;
        end;
d:=d*2+1;
assign(f,'fractii.out');rewrite(f);
write(f,d);
close(f);
end.