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%I #7 Dec 12 2018 06:51:47
%S 476,320,419,632,932,1318,1855,2528,3408,4498,5864,7521,9542,11949,
%T 14824,18197,22158,26745,32056,38137,45094,52981,61912,71949,83214,
%U 95777,109768,125265,142406,161277,182024,204741,229582,256649,286104,318057
%N Number of (n+1) X (6+1) 0..1 arrays with every 2 X 2 subblock antidiagonal maximum minus diagonal minimum nondecreasing horizontally and diagonal maximum minus antidiagonal minimum nondecreasing vertically.
%H R. H. Hardin, <a href="/A253395/b253395.txt">Table of n, a(n) for n = 1..210</a>
%F Empirical: a(n) = 4*a(n-1) - 5*a(n-2) + 5*a(n-4) - 4*a(n-5) + a(n-6) for n>16.
%F Empirical for n mod 2 = 0: a(n) = (1/6)*n^4 + (185/6)*n^2 - 61*n + 357 for n>10.
%F Empirical for n mod 2 = 1: a(n) = (1/6)*n^4 + (185/6)*n^2 - 61*n + 364 for n>10.
%F Empirical g.f.: x*(476 - 1584*x + 1519*x^2 + 556*x^3 - 1881*x^4 + 1054*x^5 - 48*x^6 - 106*x^7 + 20*x^8 + 12*x^9 - 23*x^10 + 17*x^11 - 5*x^12 + 2*x^14 - x^15) / ((1 - x)^5*(1 + x)). - _Colin Barker_, Dec 12 2018
%e Some solutions for n=4:
%e ..0..1..0..1..0..1..1....1..1..1..0..0..0..1....1..1..1..1..1..1..1
%e ..0..1..0..1..0..1..0....1..1..1..1..1..1..1....1..1..1..0..0..0..0
%e ..0..1..0..1..0..1..0....1..1..0..0..0..0..0....1..1..1..1..1..1..1
%e ..0..1..0..1..0..1..0....1..1..1..1..1..1..1....1..0..0..0..0..0..0
%e ..0..1..0..1..0..1..0....0..0..0..0..0..0..0....0..0..1..1..1..1..1
%Y Column 6 of A253397.
%K nonn
%O 1,1
%A _R. H. Hardin_, Dec 31 2014
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