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Number of (n+1) X (7+1) 0..2 arrays with no 2X2 2 X 2 subblock having the sum of its diagonal elements greater than the absolute difference of its antidiagonal elements.

Column 7 of A251088

Empirical: a(n) = 6*a(n-1) - 13*a(n-2) + 10*a(n-3) + 5*a(n-4) - 14*a(n-5) + 9*a(n-6) - 2*a(n-7) for n>8.

Empirical g.f.: x*(3593 - 12472*x + 7604*x^2 + 18338*x^3 - 32161*x^4 + 17566*x^5 - 1962*x^6 - 756*x^7) / ((1 - x)^5*(1 + x)*(1 - 2*x)). - Colin Barker, Nov 24 2018

Some solutions for n=4:

Column 7 of A251088.

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R. H. Hardin, <a href="/A251087/b251087.txt">Table of n, a(n) for n = 1..210</a>

allocated for R. H. Hardin

Number of (n+1)X(7+1) 0..2 arrays with no 2X2 subblock having the sum of its diagonal elements greater than the absolute difference of its antidiagonal elements

3593, 9086, 15411, 28616, 48017, 82898, 139553, 240972, 420611, 755534, 1387095, 2607904, 4990157, 9687898, 18995941, 37513316, 74424559, 148107894, 295305995, 589513112, 1177703721, 2353835426, 4705809161, 9409435196, 18816319547

1,1

Column 7 of A251088

Empirical: a(n) = 6*a(n-1) -13*a(n-2) +10*a(n-3) +5*a(n-4) -14*a(n-5) +9*a(n-6) -2*a(n-7) for n>8

Some solutions for n=4

..0..0..0..1..0..0..1..2....1..0..0..2..0..1..0..2....0..1..0..1..0..0..0..2

..0..0..0..1..0..0..0..0....1..0..0..2..0..1..0..1....0..1..0..1..0..0..0..1

..0..0..0..1..0..0..0..0....1..0..0..2..0..1..0..1....0..1..0..1..0..0..0..0

..1..0..0..1..0..0..0..0....1..0..0..2..0..1..0..1....0..1..0..1..0..0..0..0

..2..1..0..1..0..0..0..0....1..0..0..2..0..1..0..0....2..1..0..1..0..0..0..0

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R. H. Hardin, Nov 29 2014

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