program fractii;
var p,q,n,s,s1,s2:integer;
    f,f1:real;
    x,g:text;
begin
assign(x,'fractii.in');
assign(g,'fractii.out');
reset(x);
reset(g);
read(x,n);
s:=0;
s1:=0;
for p:=1 to n do begin
for q:=1 to n do begin
    if p>=q then begin
       f:=p/q;
       s:=s+1;end
       else if q>p then begin
       f1:=q/p;
       s1:=s1+1;end;
s2:=s+s1; end;end;
write(g,s2);
close(x);
close(g);
end.