Find the number of options to paint m (or more) pixels in a pixel row with n pixels

Question_4.py

def number_of_paint_options(n, m):
	def find_num_options(n, m):
		'''Find the number of options to paint m (or more) pixels in a pixel row with n pixels'''
		return 1 + sum((k - m + 1) * find_num_options(n - k - 1, m) for k in range(m, n + 1))
	if m > n or m == 0:
		return 0
	elif n == m:
		return 1
	return find_num_options(n, m)

if m == 0: return 0
Personal preference, different then question requirements.