# jemdoc: addcss{rbh.css}, addcss{jacob.css}
= collatz conjecture

conjecture: for every positive integer n, 
the loop terminates, 
and the last number printed is 1

[http://xkcd.com/710/ xkcd]
[http://en.wikipedia.org/wiki/Collatz_conjecture wiki]

odd pix:
[http://webdocs.cs.ualberta.ca/~hayward/272/jem/figs/c25.pdf 25]
[http://webdocs.cs.ualberta.ca/~hayward/272/jem/figs/c99.pdf 99]
[http://webdocs.cs.ualberta.ca/~hayward/272/jem/figs/c199.pdf 199]
[http://webdocs.cs.ualberta.ca/~hayward/272/jem/figs/c299.pdf 299]
[http://webdocs.cs.ualberta.ca/~hayward/272/jem/figs/c399.pdf 399]
[http://webdocs.cs.ualberta.ca/~hayward/272/jem/figs/c499.pdf 499]
[http://webdocs.cs.ualberta.ca/~hayward/272/jem/figs/c599.pdf 599]
[http://webdocs.cs.ualberta.ca/~hayward/272/jem/figs/c699.pdf 699]
[http://webdocs.cs.ualberta.ca/~hayward/272/jem/figs/c799.pdf 799]
[http://webdocs.cs.ualberta.ca/~hayward/272/jem/figs/c899.pdf 899]
[http://webdocs.cs.ualberta.ca/~hayward/272/jem/figs/c999.pdf 999]

~~~
{def collatz(n):}{}
    while n > 1:
        print n
        if n % 2 == 0:
            n = n / 2
        else:
            n = n * 3 + 1
    print n
~~~