https://projecteuler.net/problem=14

euler14.py

terms = [None] * 1000001

maxterms = 0
maxtermsNum = 0

for i in range(1,1000001):
	c = i
	count = 1
	while c > 1:
		if c % 2 == 0:
			c = c / 2
		else:
			c = c * 3 + 1
		if c < i:
			count = count + terms[c]
			break
		count = count + 1
	terms[i] = count
	if count > maxterms:
		maxterms = count
		maxtermsNum = i
	
print maxtermsNum, maxterms