014.py


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def chain_len(n):
	count = 1
	while(n != 1):
		if not n & 1:
			n = n / 2
		else:
			n = 3*n + 1
		count += 1
	return count

max_len = 0
max_start = 0

for i in range(1, 1000000):
	len = chain_len(i)
	if len > max_len:
		max_start = i
		max_len = len

print max_start