

A246310


Number of ON cells at generation n of 2D cellular automaton in which a cell is ON iff either 1 or 4 of its eight neighbors were ON at previous generation, starting with a single ON cell.


2



1, 8, 8, 25, 4, 32, 32, 100, 25, 61, 88, 208, 112, 164, 232, 380, 188, 304, 341, 596, 437, 576, 528, 696, 553, 749, 736, 924, 1016, 1060, 1161, 1372, 1200, 1388, 1456, 1720, 1493, 1761, 1660, 2072, 1781, 2084, 1973, 2732, 2252, 2596, 2552, 3121, 2684, 3145, 2972, 3828, 3132, 3588, 3480, 4061, 3772, 4073, 4009, 4929, 4264, 4996, 4845, 5493, 5160, 5804, 5156
(list;
graph;
refs;
listen;
history;
text;
internal format)



OFFSET

0,2


COMMENTS

This is the Rule 780 outer totalistic 8neighbor 2D CA.
The first few generations are easy to understand, but then there are complications (hence the keyword "look", which refers to the illustrations).


LINKS

Table of n, a(n) for n=0..66.
N. J. A. Sloane, Illustration of first 28 generations.
N. J. A. Sloane, On the Number of ON Cells in Cellular Automata, arXiv:1503.01168, 2015


MATHEMATICA

Total@*Total /@ CellularAutomaton[{780, {2, {{2, 2, 2}, {2, 1, 2}, {2, 2, 2}}}, {1, 1}}, {{{1}}, 0}, 66]
ArrayPlot /@ CellularAutomaton[{780, {2, {{2, 2, 2}, {2, 1, 2}, {2, 2, 2}}}, {1, 1}}, {{{1}}, 0}, 28]


CROSSREFS

Cf. A253086 (5celled analog).
Sequence in context: A160239 A211017 A037018 * A318542 A319089 A003873
Adjacent sequences: A246307 A246308 A246309 * A246311 A246312 A246313


KEYWORD

nonn,look


AUTHOR

N. J. A. Sloane, Aug 23 2014


STATUS

approved



