def recursive_dichotomy(list, value, beginning, end):
  """
  list: array of integers in ascending order
  value: value to return its position in the list
  beginning: first index of list (in this case 0)
  end: last index of list (in this case len(list))
  return: False in value not in list, else the position of value in the list
  """
  middle = (beginning+end)//2
  if value not in list:
    return False
  if list[middle] == value:
    return middle
  elif value > list[middle]:
    return recursive_dichotomy(list, value, middle, end)
  elif value < list[middle]:
    return recursive_dichotomy(list, value, beginning, middle)