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A253075 Number of ON cells at generation n in a certain two-dimensional cellular automaton that produces a roughly circular pattern. 1

%I

%S 7,17,27,31,39,51,63,79,83,89,101,115,123,139,159,191,207,219,235,261,

%T 273,287,313,349,373,401,425,457,489,523,559,579,607,633,667,691,733,

%U 771,817,855,891,931,977,1007,1037,1079,1141,1191,1241

%N Number of ON cells at generation n in a certain two-dimensional cellular automaton that produces a roughly circular pattern.

%C This is the CA on the square grid, defined by Rule 175850, and started with 7 adjacent ON cells. It is shown on page 177 of Wolfram's A New Kind of Science.

%H N. J. A. Sloane, <a href="/A253075/a253075.png">Illustration of initial terms</a>

%H S. Wolfram, <a href="http://www.wolframscience.com/nksonline/page-177">A New Kind of Science, Wolfram Media Inc., (2002), p. 177</a>

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

%t ArrayPlot /@ CellularAutomaton[{175850, {2, {{2, 2, 2}, {2, 1, 2}, {2, 2, 2}}}, {1, 1}}, {{{1, 1, 1, 1, 1, 1, 1}}, 0}, 16] (Produces illustrations)

%t Total@*Total /@ CellularAutomaton[{175850, {2, {{2, 2, 2}, {2, 1, 2}, {2, 2, 2}}}, {1, 1}}, {{{1, 1, 1, 1, 1, 1, 1}}, 0}, 32] (Produces sequence)

%K nonn

%O 0,1

%A _N. J. A. Sloane_, Feb 01 2015

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Last modified December 4 02:40 EST 2021. Contains 349469 sequences. (Running on oeis4.)