

A267776


Triangle read by rows giving successive states of cellular automaton generated by "Rule 209" initiated with a single ON (black) cell.


2



1, 0, 0, 1, 1, 1, 0, 0, 1, 1, 1, 1, 1, 0, 0, 1, 1, 1, 1, 1, 1, 1, 0, 0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 0, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 1, 0, 0, 1, 1, 1, 1, 1, 1
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OFFSET

0


COMMENTS

Row n has length 2n+1.
This sequence is also generated by Rule 241.


REFERENCES

S. Wolfram, A New Kind of Science, Wolfram Media, 2002; p. 55.


LINKS

Robert Price, Table of n, a(n) for n = 0..10000
Eric Weisstein's World of Mathematics, Elementary Cellular Automaton
S. Wolfram, A New Kind of Science
Index entries for sequences related to cellular automata
Index to Elementary Cellular Automata


EXAMPLE

The first ten rows:
1
0 0 1
1 1 0 0 1
1 1 1 1 0 0 1
1 1 1 1 1 1 0 0 1
1 1 1 1 1 1 1 1 0 0 1
1 1 1 1 1 1 1 1 1 1 0 0 1
1 1 1 1 1 1 1 1 1 1 1 1 0 0 1
1 1 1 1 1 1 1 1 1 1 1 1 1 1 0 0 1
1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 1 0 0 1


MATHEMATICA

rule=209; rows=20; ca=CellularAutomaton[rule, {{1}, 0}, rows1, {All, All}]; (* Start with single black cell *) catri=Table[Take[ca[[k]], {rowsk+1, rows+k1}], {k, 1, rows}]; (* Truncated list of each row *) Flatten[catri] (* Triangle Representation of CA *)


CROSSREFS

Sequence in context: A004609 A287674 A071001 * A072792 A254113 A267037
Adjacent sequences: A267773 A267774 A267775 * A267777 A267778 A267779


KEYWORD

nonn,tabf,easy


AUTHOR

Robert Price, Jan 20 2016


STATUS

approved



