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A070886 Triangle read by rows giving successive states of cellular automaton generated by "Rule 90".

%I A070886 #24 Feb 16 2025 08:32:46
%S A070886 1,1,0,1,1,0,0,0,1,1,0,1,0,1,0,1,1,0,0,0,0,0,0,0,1,1,0,1,0,0,0,0,0,1,
%T A070886 0,1,1,0,0,0,1,0,0,0,1,0,0,0,1,1,0,1,0,1,0,1,0,1,0,1,0,1,0,1,1,0,0,0,
%U A070886 0,0,0,0,0,0,0,0,0,0,0,0,1,1,0,1,0,0,0,0,0,0,0,0,0,0,0,0,0,1,0
%N A070886 Triangle read by rows giving successive states of cellular automaton generated by "Rule 90".
%C A070886 If either neighbor is 1 then new state is 1, otherwise new state is 0.
%C A070886 Row n has length 2n+1.
%C A070886 Rules #18, #26, #82, #90, #146, #154, #210, #218 all give rise to this sequence. - Hans Havermann
%D A070886 S. Wolfram, A New Kind of Science, Wolfram Media, 2002; p. 25.
%H A070886 Robert Price, <a href="/A070886/b070886.txt">Table of n, a(n) for n = 0..9999</a>
%H A070886 Eric Weisstein's World of Mathematics, <a href="https://mathworld.wolfram.com/Rule90.html">Rule 90</a>
%H A070886 S. Wolfram, <a href="http://wolframscience.com/">A New Kind of Science</a>
%H A070886 <a href="https://oeis.org/wiki/Index_to_Elementary_Cellular_Automata">Index to Elementary Cellular Automata</a>
%H A070886 <a href="/index/Ce#cell">Index entries for sequences related to cellular automata</a>
%e A070886 1; 1,0,1; 1,0,0,0,1; 1,0,1,0,1,0,1; ...
%t A070886 rows = 10; ca = CellularAutomaton[90, {{1}, 0}, rows-1]; Flatten[ Table[ca[[k, rows-k+1 ;; rows+k-1]], {k, 1, rows}]] (* _Jean-François Alcover_, May 24 2012 *)
%Y A070886 Cf. A070950, A070887. Alternate rows of A047999. Interpreted as binary numbers: A038183. Interpreted as Zeckendorf-expansions: A048757. Drawn as binary trees: A080263.
%K A070886 nonn,tabf,nice,easy
%O A070886 0,1
%A A070886 _N. J. A. Sloane_, May 19 2002
%E A070886 More terms from _Hans Havermann_, May 26 2002