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 A267725 Number of 2Xn arrays containing n copies of 0..2-1 with every element equal to at least one horizontal neighbor and the top left element equal to 0. 2
 0, 1, 1, 3, 5, 12, 26, 60, 143, 353, 879, 2200, 5528, 13963, 35421, 90122, 229729, 586438, 1498966, 3836099, 9827905, 25202549, 64683193, 166137751, 427022480, 1098291533, 2826500851, 7278246356, 18751418071, 48334451894, 124647030884 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,4 COMMENTS Row 2 of A267724. LINKS R. H. Hardin, Table of n, a(n) for n = 1..210 EXAMPLE Some solutions for n=6 ..0..0..1..1..0..0....0..0..1..1..1..1....0..0..1..1..0..0....0..0..0..0..0..0 ..0..0..1..1..1..1....0..0..0..0..1..1....1..1..1..1..0..0....1..1..1..1..1..1 CROSSREFS Cf. A267724. Sequence in context: A017921 A280000 A241097 * A161762 A245649 A291035 Adjacent sequences: A267722 A267723 A267724 * A267726 A267727 A267728 KEYWORD nonn AUTHOR R. H. Hardin, Jan 20 2016 STATUS approved

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Last modified August 7 06:13 EDT 2024. Contains 375008 sequences. (Running on oeis4.)