

A261990


Color of the cell Langton's Ant touches on its nth 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
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OFFSET

0


COMMENTS

The ant starts from a completely white grid.
There are never more than 4 0s or 1s in a row because 4 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



