How can I create a random walk animation with animation nodes? The idea is to have a bunch of objects that are animated given a random vector each 20 frames. Something like this video:

https://vimeo.com/75135375

The problem that I´ve found with Animation Nodes is how to somehow store the previous positions of the objects that sometimes could be 20 frames away. For the first animation I can use the ID key, but as long as the animation continues I can keep it consistent.
Currently there is no very efficient way to do this. 

If you only have a few objects this solution might work for you:



Essentially you generate the whole path for each object in each frame.