Liam's house has a staircase with 12 steps. He can go down the steps one at a time or two at time.
For example: He could go down 1 step, then one step, then 2 steps, then 2, 2, 1, 1, 1, 1.

In how many different ways can Liam go down the 12 steps, taking one or two steps at a time?