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+import PIL
+import math
+
+# Problem 14 Longest Collatz sequence
+# Note, a little slow, takes about 15 seconds.
+# There is probably a more efficient solution out there
+chain = []
+biggo = []
+
+
+def collatz(seed):
+ chain.append(seed)
+ if(seed == 1):
+ return 0
+ if(seed % 2 == 0):
+ seed = seed/2
+ else:
+ seed = 3*seed + 1
+ collatz(seed)
+
+
+for n in range(1, pow(10, 6)):
+ collatz(n)
+ if(len(chain) > len(biggo)):
+ biggo = chain
+ chain = []
+print(biggo)
+print("Has " + str(len(biggo)) + " numbers.")