path: root/progs/a466.py

def eulerian_num(n, m): 
	if (m >= n or n == 0): 
		return 0 
	if (m == 0): 
		return 1 
	return ((n - m) * eulerian_num(n - 1, m - 1) +(m + 1) * eulerian_num(n - 1, m))