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A070886 Triangle read by rows giving successive states of cellular automaton generated by "Rule 90". 8
1, 1, 0, 1, 1, 0, 0, 0, 1, 1, 0, 1, 0, 1, 0, 1, 1, 0, 0, 0, 0, 0, 0, 0, 1, 1, 0, 1, 0, 0, 0, 0, 0, 1, 0, 1, 1, 0, 0, 0, 1, 0, 0, 0, 1, 0, 0, 0, 1, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 0, 1, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 1, 0, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 0 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,1

COMMENTS

If either neighbor is 1 then new state is 1, otherwise new state is 0.

Row n has length 2n+1.

Rules #18, #26, #82, #90, #146, #154, #210, #218 all give rise to this sequence. - Hans Havermann

REFERENCES

S. Wolfram, A New Kind of Science, Wolfram Media, 2002; p. 25.

LINKS

Robert Price, Table of n, a(n) for n = 0..9999

Eric Weisstein's World of Mathematics, Rule 90

S. Wolfram, A New Kind of Science

Index to Elementary Cellular Automata

Index entries for sequences related to cellular automata

EXAMPLE

1; 1,0,1; 1,0,0,0,1; 1,0,1,0,1,0,1; ...

MATHEMATICA

rows = 10; ca = CellularAutomaton[90, {{1}, 0}, rows-1]; Flatten[ Table[ca[[k, rows-k+1 ;; rows+k-1]], {k, 1, rows}]] (* Jean-François Alcover, May 24 2012 *)

CROSSREFS

Cf. A070950, A070887. Alternate rows of A047999. Interpreted as binary numbers: A038183. Interpreted as Zeckendorf-expansions: A048757. Drawn as binary trees: A080263.

Sequence in context: A039966 A089451 A145099 * A041004 A141736 A134842

Adjacent sequences:  A070883 A070884 A070885 * A070887 A070888 A070889

KEYWORD

nonn,tabf,nice,easy

AUTHOR

N. J. A. Sloane, May 19 2002

EXTENSIONS

More terms from Hans Havermann, May 26 2002

STATUS

approved

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Last modified November 19 11:04 EST 2017. Contains 294936 sequences.