A263428 - OEIS

%I #39 Aug 31 2021 19:32:15

%S 1,1,0,0,0,0,0,1,0,1,1,1,1,0,0,1,0,0,0,0,0,0,1,0,0,1,1,1,1,1,1,1,0,0,

%T 1,1,0,0,0,0,0,0,0,0,0,1,0,0,0,1,1,1,1,1,1,1,1,1,1,0,0,1,1,1,0,0,0,0,

%U 0,0,0,0,0,0,0,0,1,0,0,0,0,1,1,1,1,1

%N Triangle read by rows giving successive states of cellular automaton generated by "Rule 3" initiated with a single ON (black) cell.

%C Row n has length 2n+1.

%C This sequence is also generated by Rule 35.

%H Robert Price, <a href="/A263428/b263428.txt">Table of n, a(n) for n = 0..9999</a>

%H Eric Weisstein's World of Mathematics, <a href="http://mathworld.wolfram.com/ElementaryCellularAutomaton.html">Elementary Cellular Automaton</a>

%H Stephen Wolfram, <a href="http://wolframscience.com/">A New Kind of Science</a>, Wolfram Media, 2002; p. 55.

%H <a href="/index/Ce#cell">Index entries for sequences related to cellular automata</a>

%H <a href="https://oeis.org/wiki/Index_to_Elementary_Cellular_Automata">Index to Elementary Cellular Automata</a>

%e The first ten rows:

%e                   1

%e                 1 0 0

%e               0 0 0 1 0

%e             1 1 1 1 0 0 1

%e           0 0 0 0 0 0 1 0 0

%e         1 1 1 1 1 1 1 0 0 1 1

%e       0 0 0 0 0 0 0 0 0 1 0 0 0

%e     1 1 1 1 1 1 1 1 1 1 0 0 1 1 1

%e   0 0 0 0 0 0 0 0 0 0 0 0 1 0 0 0 0

%e 1 1 1 1 1 1 1 1 1 1 1 1 1 0 0 1 1 1 1

%t rule = 3; rows = 20; Flatten[Table[Take[CellularAutomaton[rule, {{1},0}, rows-1, {All, All}][[k]], {rows - k + 1, rows + k - 1}], {k, 1, rows}]]

%Y Cf. A266068, A266069, A266070 (middle column), A260552 (rows reversed).

%K nonn,tabf,easy

%O 0

%A _Robert Price_, Dec 20 2015