def lookNsay():
	'''Generate the "look and say" sequence:
	1, 11, 21, 1211, 111221, 312211, 13112221, 1113213211, ...
	Note that strings are returned
	'''
	s = '1'				# s is the previous result, start with 1
	while True:
		yield s
		c,n, result = s[0], 1, ''
		for t in s[1:]:
			if t==c:
				n += 1
			else:
				result += str(n) + c
				c,n = t, 1
		result += str(n) + c
		s = result


def saythis(prev): # Supporting function
	'''Generate characters of a "look-and-say" number given a generator of
	characters for the previous number.
	'''
	c,n = next(prev), 1
	for t in prev:
		if t==c:
			n += 1
		else:
			yield str(n)
			yield c
			c,n = t, 1
	yield str(n)
	yield c
	
	
def lookNsayNth(n = 1):
	'''Generate characters of the n-th value of the "look-and-say" sequence
	recursively
	'''
	if n == 1:
		yield '1'
	else:
		yield from saythis(lookNsayNth(n-1))