Martínez, G. J., McIntosh, H. V., Seck-Tuoh-Mora, J. C., & Chapa-Vergara, S. V. (2008). Determining a Regular Language by Glider-Based Structures called Phases f(i)-1 in Rule 110. Journal of Cellular Automata, 3, 231-270.
Rule 110 is a complex elementary cellular automaton able of support universal computation and complicated collision-based reactions between gliders. We propose a representation for coding initial conditions by means of a finite subset of regular expressions. The sequences are extracted both from de Bruijn diagrams and tiles specifying a set of phases f i_1 for each glider in Rule 110. The subset of regular expressions is explained in detail.