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A253393
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Number of (n+1) X (4+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.
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1
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180, 197, 246, 346, 465, 632, 823, 1071, 1351, 1695, 2079, 2535, 3039, 3623, 4263, 4991, 5783, 6671, 7631, 8695, 9839, 11095, 12439, 13903, 15463, 17151, 18943, 20871, 22911, 25095, 27399, 29855, 32439, 35183, 38063, 41111, 44303, 47671, 51191, 54895
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OFFSET
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1,1
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LINKS
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R. H. Hardin, Table of n, a(n) for n = 1..210
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FORMULA
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Empirical: a(n) = 3*a(n-1) - 2*a(n-2) - 2*a(n-3) + 3*a(n-4) - a(n-5) for n>11.
Empirical for n mod 2 = 0: a(n) = (2/3)*n^3 + 7*n^2 + (70/3)*n + 95 for n>6.
Empirical for n mod 2 = 1: a(n) = (2/3)*n^3 + 7*n^2 + (70/3)*n + 88 for n>6.
Empirical g.f.: x*(180 - 343*x + 15*x^2 + 362*x^3 - 227*x^4 + 10*x^5 + 8*x^6 + 4*x^7 - x^8 - x^9 + x^10) / ((1 - x)^4*(1 + x)). - Colin Barker, Dec 11 2018
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EXAMPLE
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Some solutions for n=4:
..0..0..0..0..0....1..1..1..1..1....1..1..1..1..1....1..1..1..1..1
..0..0..0..0..0....1..1..1..1..1....1..1..1..1..1....1..1..1..1..1
..0..0..0..0..0....1..1..1..1..0....1..1..1..1..1....1..1..1..0..0
..0..0..0..1..0....1..1..1..1..1....1..1..1..1..1....1..1..1..1..1
..1..1..0..1..0....0..1..0..0..0....0..1..1..1..0....1..0..0..0..0
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CROSSREFS
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Column 4 of A253397.
Sequence in context: A053325 A119542 A154360 * A260265 A117551 A068545
Adjacent sequences: A253390 A253391 A253392 * A253394 A253395 A253396
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KEYWORD
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nonn
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AUTHOR
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R. H. Hardin, Dec 31 2014
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STATUS
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approved
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