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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
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 A353812
KEYWORD
easy,nonn
AUTHOR
STATUS
approved