var i,n,j,x,y,k:longint;
    a:array[1..5000] of longint;
    f,g:text;
begin
 assign(f,'pairs.in');
 reset(f);
 readln(f,n);
 for i:=1 to n do
  readln(f,a[i]);
 close(f);
 k:=0;
 for i:=1 to n-1 do
  for j:=i to n do
   if a[i]<>a[j] then begin
    x:=a[i];
    y:=a[j];
    while x<>y do
     if x>y then x:=x-y
      else y:=y-x;
    if x=1 then inc(k);
    end;
 assign(g,'pairs.out');
 rewrite(g);
 write(g,k);
 close(g);
end.