In the mathematical study of cellular automata, Rule 90 is an elementary cellular automaton based on the exclusive or function, call it "the simplest non-trivial cellular automaton", and it is described extensively in Stephen Wolfram's book, released in what year, "A New Kind of Science", Wolfram, a British-American computer scientist, physicist, and businessman?
Rule 90 In the mathematical study of cellular automata, Rule 90 is an elementary cellular automaton based on the exclusive or function. It consists of a one-dimensional array of cells, each of which can hold either a 0 or a 1 value. In each time step all values are simultaneously replaced by the exclusive or of their two neighboring values. call it "the simplest non-trivial cellular automaton", and it is described extensively in Stephen Wolfram's 2002 book "A New Kind of Science".
Wilson prime A Wilson prime, named after English mathematician John Wilson, is a prime number "p" such that "p" divides ("p" − 1)! + 1, where "!" denotes the factorial function; compare this with Wilson's theorem, which states that every prime "p" divides ("p" − 1)! + 1.