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A221653 Number of n X 3 arrays of occupancy after each element moves to some horizontal, diagonal or antidiagonal neighbor, without move-in move-out left turns. 1
2, 24, 230, 2594, 28478, 313721, 3449644, 37942960, 417316514, 4589956344, 50483589902, 555254580431, 6107085156536, 67170072001106, 738784285695336, 8125675702282959, 89371968083241970, 982976551394628990 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Column 3 of A221655.

LINKS

R. H. Hardin, Table of n, a(n) for n = 1..40

EXAMPLE

Some solutions for n=3

..0..1..2....0..3..1....2..2..0....0..2..0....1..2..0....0..1..1....1..2..0

..1..2..0....0..2..2....0..0..0....1..2..1....1..3..1....0..1..1....0..3..1

..0..3..0....0..1..0....1..4..0....0..2..1....0..1..0....1..4..0....0..1..1

CROSSREFS

Cf. A221655.

Sequence in context: A147538 A180388 A288270 * A219205 A025131 A270564

Adjacent sequences:  A221650 A221651 A221652 * A221654 A221655 A221656

KEYWORD

nonn

AUTHOR

R. H. Hardin Jan 21 2013

STATUS

approved

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Last modified December 1 11:07 EST 2021. Contains 349429 sequences. (Running on oeis4.)