Collatz Conjecture

collatz.py

import random

def collatz(n):
    """                                                                                                                                                      
    Run the collatz conjecture for integer n                                                                                                                 
    http://en.wikipedia.org/wiki/Collatz_conjecture                                                                                                          
    """

    step = lambda m: m * 3 + 1 if m % 2 else m / 2

    i = 0
    while n != 1:
        print n
        n = step(n)
    return i

def main():
    start = random.randint(0, 100000)
    steps = collatz(start)
    print "The number %i was converged to 1 in %i steps." % (start, steps)

if __name__ == "__main__":
    main()