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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
Eric Weisstein's World of Mathematics, Rule 90
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: A089451 A145099 A205083 * A262808 A217206 A189097
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 March 29 08:13 EDT 2024. Contains 371265 sequences. (Running on oeis4.)