A265172 Binary representation of the n-th iteration of the "Rule 90" elementary cellular automaton starting with a single ON (black) cell.

1, 101, 10001, 1010101, 100000001, 10100000101, 1000100010001, 101010101010101, 10000000000000001, 1010000000000000101, 100010000000000010001, 10101010000000001010101, 1000000010000000100000001, 101000001010000010100000101, 10001000100010001000100010001

Offset

0,2

Comments

Rules 26, 82, 90, 146, 154, 210 and 218 also generate this sequence.

References

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

Links

Robert Price, Table of n, a(n) for n = 0..999

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

Mathematica

rule = 90; rows = 20; Table[FromDigits[Table[Take[CellularAutomaton[rule, {{1}, 0}, rows-1, {All, All}][[k]], {rows-k+1, rows+k-1}], {k, 1, rows}][[k]]], {k, 1, rows}]

Crossrefs

Cf. A070886.

Sequence in context: A291990 A303572 A152756 * A153500 A262861 A371563

Adjacent sequences: A265169 A265170 A265171 * A265173 A265174 A265175

Keyword

nonn,easy

Author

Robert Price, Dec 05 2015

Status

approved