Chapter 5: Two Dimensions and Beyond

Section 7: Systems Based on Constraints

Sequence equations

Another way to set up 1D systems based on constraints is by having equations like Flatten[{x,1,x,0,y}]===Flatten[{0,y,0,y,x}], where each variable stands for a list. Fairly simple such equations can force fairly complicated results, although as discussed on page 1141 there are known to be limits to this complexity.

From Stephen Wolfram: A New Kind of Science [citation]