program fractii;
var f:text;
    p,k,n,nr,a,b:longint;
begin
assign(f,'fractii.in');reset(f);
read(f,n);close(f);
nr:=1+2*(n-1);
for p:=2 to n do
     for k:=2 to p-1 do begin
           a:=p;b:=k;
           while a*b<>0 do
               if a>b then a:=a mod b
                      else b:=b mod a;
           if a+b=1 then nr:=nr+2;
           end;
assign(f,'fractii.out');rewrite(f);
write(f,nr);close(f);
end.