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 A297721 Number of 2Xn 0..1 arrays with every 1 horizontally, diagonally or antidiagonally adjacent to 1, 2 or 4 neighboring 1s. 1
 1, 10, 34, 83, 258, 865, 2651, 8041, 25114, 78356, 242335, 750668, 2331147, 7233125, 22428585, 69571574, 215837630, 669523807, 2076792418, 6442276953, 19984194983, 61990893369, 192295766302, 596503969480, 1850361240315, 5739832532268 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,2 COMMENTS Row 2 of A297720. LINKS R. H. Hardin, Table of n, a(n) for n = 1..210 FORMULA Empirical: a(n) = 4*a(n-1) -3*a(n-2) +3*a(n-3) -2*a(n-4) -24*a(n-5) +24*a(n-6) EXAMPLE Some solutions for n=7 ..1..1..0..1..1..0..0. .0..0..1..0..1..1..1. .0..1..0..1..1..0..0 ..1..1..0..0..0..1..1. .0..0..1..1..1..0..1. .1..0..0..1..0..0..0 CROSSREFS Cf. A297720. Sequence in context: A007584 A218329 A009924 * A019257 A288782 A020877 Adjacent sequences:  A297718 A297719 A297720 * A297722 A297723 A297724 KEYWORD nonn AUTHOR R. H. Hardin, Jan 04 2018 STATUS approved

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Last modified December 14 17:09 EST 2018. Contains 318103 sequences. (Running on oeis4.)