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A269480
Number of 3Xn arrays containing n copies of 0..3-1 avoiding the pattern down-up in every row and equal-up in every column.
1
4, 54, 574, 6404, 72110, 816583, 9323584, 107089479, 1236171969, 14324836704, 166516037345, 1940477033553, 22659370920439, 265044574417791, 3104569328697374, 36408281098910933, 427405044547342278
OFFSET
1,1
COMMENTS
Row 3 of A269479.
LINKS
EXAMPLE
Some solutions for n=4
..2..0..1..0. .1..1..0..0. .2..0..1..2. .2..0..1..1. .1..0..2..0
..2..1..1..0. .2..1..0..0. .2..0..1..2. .2..0..2..2. .1..2..1..0
..0..2..2..1. .1..2..2..2. .1..1..0..0. .0..1..0..1. .0..2..1..2
CROSSREFS
Cf. A269479.
Sequence in context: A302942 A292305 A073863 * A199022 A221395 A357558
KEYWORD
nonn
AUTHOR
R. H. Hardin, Feb 27 2016
STATUS
approved