xkcd (http://xkcd.com/710/) inspired Colltaz Conjecture exploration (http://en.wikipedia.org/wiki/Collatz_conjecture)

collatz.lua

-- Lack of easy access to anything better than second resolution.  Blah.
math.randomseed(os.time())
-- Successive seeds of os.time() that are close end up creating the same
-- value on OSX due to the integer making or random(x,y) losing precision
math.randomseed(os.time() * math.random())
local num = math.random(1e7,1e8)

while num ~= 1 do
	str = "" .. num
	if num % 2 == 0 then
		num = num / 2
		str = str .. " / 2"
	else
		num = (num * 3) + 1
		str = str .. " * 3 + 1"
	end
	print(str)
end

print(num)