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A308973 Langton's ant on a truncated square tiling: number of black cells after n moves of the ant when starting on an octagon and looking towards an edge where the tile meets another octagon. 8
0, 1, 2, 3, 4, 5, 6, 5, 6, 7, 8, 9, 8, 7, 8, 9, 10, 11, 10, 11, 10, 9, 10, 11, 12, 13, 14, 15, 14, 15, 16, 17, 18, 17, 16, 17, 18, 17, 16, 17, 18, 19, 20, 21, 22, 21, 22, 23, 24, 23, 22, 23, 24, 25, 26, 27, 28, 27, 28, 29, 30, 29, 28, 29, 30, 31, 32, 33, 34 (list; graph; refs; listen; history; text; internal format)
OFFSET
0,3
COMMENTS
First differs from A269757 at n = 19.
On a white square, turn 90 degrees right, flip the color of the tile, then move forward one unit.
On a white octagon, turn 45 degrees right, flip the color of the tile, then move forward one unit.
On a black square, turn 90 degrees left, flip the color of the tile, then move forward one unit.
On a black octagon, turn 45 degrees left, flip the color of the tile, then move forward one unit.
As in the original variant, order emerges after a transition phase and the ant starts building a recurrent "highway" pattern of 12 steps that repeats indefinitely. - Rémy Sigrist, Jul 21 2019
LINKS
Wikipedia, Langton's ant
FORMULA
a(n + 12) = a(n) + 6 for any n >= 34. - Rémy Sigrist, Jul 21 2019
EXAMPLE
See illustrations in Fröhlich, 2019.
PROG
(PARI) See Links section.
CROSSREFS
Sequence in context: A102730 A165597 A269757 * A309279 A245352 A099033
KEYWORD
nonn
AUTHOR
Felix Fröhlich, Jul 04 2019
EXTENSIONS
More terms from Rémy Sigrist, Jul 21 2019
STATUS
approved

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Last modified March 28 03:28 EDT 2024. Contains 371235 sequences. (Running on oeis4.)