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Number of (n+2) X (3+2) 0..1 arrays with every 2X2 2 X 2 and 3X3 3 X 3 subblock diagonal maximum minus antidiagonal minimum unequal to its neighbors horizontally and vertically.
Column 3 of A253367
Empirical: a(n) = 7*a(n-2) - 15*a(n-4) + 17*a(n-6) + 16*a(n-8) for n>11.
Empirical g.f.: 8*x*(70 + 120*x - 116*x^2 - 180*x^3 + 157*x^4 + 564*x^5 + 282*x^6 + 480*x^7 - x^8 + 24*x^9 - 36*x^10) / (1 - 7*x^2 + 15*x^4 - 17*x^6 - 16*x^8). - Colin Barker, Dec 11 2018
Some solutions for n=4:
Column 3 of A253367.
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R. H. Hardin, <a href="/A253362/b253362.txt">Table of n, a(n) for n = 1..210</a>
allocated for R. H. Hardin
Number of (n+2)X(3+2) 0..1 arrays with every 2X2 and 3X3 subblock diagonal maximum minus antidiagonal minimum unequal to its neighbors horizontally and vertically
560, 960, 2992, 5280, 13800, 27072, 63496, 130464, 297288, 612480, 1410760, 2875104, 6716232, 13589568, 31922056, 64500000, 151450440, 306332928, 718070344, 1453854816, 3404870472, 6895922880, 16148448520, 32703297696
1,1
Column 3 of A253367
Empirical: a(n) = 7*a(n-2) -15*a(n-4) +17*a(n-6) +16*a(n-8) for n>11
Some solutions for n=4
..0..0..0..0..0....1..0..0..0..0....1..0..0..0..1....0..1..0..1..0
..0..1..0..1..0....0..1..0..1..0....0..1..0..1..0....1..0..0..0..0
..1..0..1..0..0....1..0..0..0..0....1..0..0..0..0....0..1..0..1..0
..0..0..0..0..0....0..1..0..1..0....0..0..0..1..0....1..0..0..0..1
..1..0..1..0..1....0..0..0..0..0....1..0..1..0..1....0..1..0..1..0
..1..1..0..1..0....0..1..0..1..0....0..0..0..1..0....0..0..0..0..1
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nonn
R. H. Hardin, Dec 30 2014
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