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 A253469 Number of (n+1) X (7+1) 0..2 arrays with every 2 X 2 subblock diagonal maximum minus antidiagonal minimum unequal to its neighbors horizontally, vertically, diagonally and antidiagonally. 1
 7227096, 44464, 17000, 15680, 20000, 20864, 32000, 41600, 80000, 124544, 272000, 456320, 1040000, 1783424, 4112000, 7091840, 16400000, 28325504, 65552000, 113260160, 262160000, 452998784, 1048592000, 1811953280, 4194320000 (list; graph; refs; listen; history; text; internal format)
 OFFSET 1,1 LINKS R. H. Hardin, Table of n, a(n) for n = 1..210 FORMULA Empirical: a(n) = 5*a(n-2) - 4*a(n-4) for n>6. Empirical g.f.: 8*x*(903387 + 5558*x - 4514810*x^2 - 25830*x^3 + 3605423*x^4 + 15040*x^5) / ((1 - x)*(1 + x)*(1 - 2*x)*(1 + 2*x)). - Colin Barker, Dec 15 2018 EXAMPLE Some solutions for n=1: ..0..0..0..1..0..2..2..2....0..0..0..0..1..0..2..1....0..0..0..2..1..1..2..2 ..1..0..1..1..0..2..0..2....2..0..2..0..2..0..2..1....2..0..1..0..2..2..1..1 CROSSREFS Column 7 of A253468. Sequence in context: A286010 A184214 A181680 * A325606 A157378 A251356 Adjacent sequences:  A253466 A253467 A253468 * A253470 A253471 A253472 KEYWORD nonn AUTHOR R. H. Hardin, Jan 01 2015 STATUS approved

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Last modified November 24 18:11 EST 2020. Contains 338616 sequences. (Running on oeis4.)