def binary_search(seq, item, min, max):
  """Recursive binary search implementation"""
  if min is max:
    return False
  midpoint = (min + max) // 2
  if seq[midpoint] == item:
    return True
  if seq[midpoint] > item:
    return binary_search(seq, item, min, midpoint)
  return binary_search(seq, item, midpoint + 1, max)