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 A269507 Number of 3Xn arrays containing n copies of 0..3-1 avoiding the pattern down-up in every row and column. 1
 4, 54, 420, 3088, 25226, 239994, 2338286, 23240168, 232006814, 2352889414, 24069853302, 248560741574, 2582277394354, 26997628173380, 283652378887212, 2994183763030920, 31727834772912212, 337396544704648686 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS Row 3 of A269505. LINKS R. H. Hardin, Table of n, a(n) for n = 1..48 EXAMPLE Some solutions for n=4 ..1..1..2..0. .1..0..0..1. .0..0..2..1. .0..0..2..2. .0..1..2..1 ..1..1..2..2. .2..1..1..2. .0..2..2..1. .1..2..1..1. .0..2..2..1 ..0..0..0..2. .0..2..2..0. .2..1..1..0. .1..2..0..0. .2..0..0..1 CROSSREFS Cf. A269505. Sequence in context: A156469 A001545 A208954 * A302942 A292305 A073863 Adjacent sequences: A269504 A269505 A269506 * A269508 A269509 A269510 KEYWORD nonn AUTHOR R. H. Hardin, Feb 28 2016 STATUS approved

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Last modified December 2 19:57 EST 2023. Contains 367526 sequences. (Running on oeis4.)