Program fractii;
var
a,k,b,p,n,nr:longint;
f:text;
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.