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 A261990 Color of the cell Langton's Ant touches on its n-th step before the color is changed by the ant; 0=white, 1=black. 6
 0, 0, 0, 0, 1, 0, 0, 0, 0, 1, 0, 0, 0, 0, 1, 1, 1, 1, 0, 1, 0, 0, 0, 0, 1, 0, 0, 0, 0, 1, 1, 1, 1, 0, 1, 0, 0, 0, 0, 1, 0, 0, 0, 0, 1, 1, 1, 1, 0, 1, 1, 0, 0, 1, 0, 0, 0, 0, 1, 1, 1, 1, 0, 1, 0, 0, 0, 0, 1, 0, 0, 0, 0, 1, 1, 1, 1, 0, 1, 0, 0, 0, 0, 1, 0, 0, 0, 0, 1, 1, 1, 1, 0, 1, 1, 0, 0, 0, 0, 1, 1, 0, 1, 0, 0, 0, 0 (list; graph; refs; listen; history; text; internal format)
 OFFSET 0 COMMENTS The ant starts from a completely white grid. There are never more than four 0's or 1's in a row because four identical turns will circle back into the same cell, which will have since changed. The sequence begins repeating at the 9977th step, in a cycle of length 104. LINKS Aaron David Fairbanks, Table of n, a(n) for n = 0..10287 Wikipedia, Langton's Ant EXAMPLE On the 0th step, the ant lands on a white square and turns it black. On the 1st step, it lands on another white square. On the 4th step, it lands on a black square, etc. CROSSREFS Cf. A126978. Sequence in context: A093957 A283317 A188041 * A144601 A188009 A144596 Adjacent sequences:  A261987 A261988 A261989 * A261991 A261992 A261993 KEYWORD easy,nonn AUTHOR Aaron David Fairbanks, Sep 07 2015 STATUS approved

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Last modified December 4 13:06 EST 2021. Contains 349526 sequences. (Running on oeis4.)