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 A280551 Number of nX5 0..1 arrays with no element equal to more than one of its horizontal and vertical neighbors, with the exception of exactly two elements, and with new values introduced in order 0 sequentially upwards. 1
 2, 87, 325, 832, 1764, 3438, 6386, 11506, 20389, 35757, 62317, 108150, 187115, 322925, 556071, 955574, 1638882, 2805542, 4794088, 8178068, 13927945, 23683803, 40214243, 68187902, 115469449, 195294823, 329919371, 556731676, 938492304 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 COMMENTS Column 5 of A280554. LINKS R. H. Hardin, Table of n, a(n) for n = 1..210 FORMULA Empirical: a(n) = 6*a(n-1) -12*a(n-2) +5*a(n-3) +12*a(n-4) -12*a(n-5) -3*a(n-6) +6*a(n-7) -a(n-9) for n>12 EXAMPLE Some solutions for n=4 ..0..1..0..1..0. .0..1..0..1..0. .0..0..1..1..1. .0..1..1..0..1 ..1..0..1..0..1. .1..1..0..0..1. .1..1..0..1..0. .1..0..0..1..1 ..0..1..1..0..0. .0..1..0..1..0. .0..0..1..0..0. .0..1..1..0..0 ..1..0..1..0..1. .1..0..1..0..1. .1..1..0..1..1. .1..0..0..1..0 CROSSREFS Cf. A280554. Sequence in context: A306139 A317372 A177318 * A283945 A172736 A244386 Adjacent sequences:  A280548 A280549 A280550 * A280552 A280553 A280554 KEYWORD nonn AUTHOR R. H. Hardin, Jan 05 2017 STATUS approved

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Last modified December 13 15:03 EST 2018. Contains 318086 sequences. (Running on oeis4.)