Langton's ant questions
There is an article on Langtons ant, published in the 
SCTPLS Newsletter ( Society for Chaos Theory in Psychology &amp; Life Sciences   Vol. 26, No. 2 February 2019 ) It introduces a first order recurrence relation for the cellular automata 'Langtons ant'   A copy can be downloaded from

http://buzwordsalad.com/lit/SCTPLS_LAWE_bw.pdf