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A258892
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Number of (n+2) X (6+2) 0..1 arrays with no 3 x 3 subblock diagonal sum less than the antidiagonal sum or central row sum less than the central column sum.
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1
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94249, 51188, 20164, 13221, 16384, 21025, 26244, 33485, 41616, 52425, 64516, 80053, 97344, 118961, 142884, 172125, 204304, 242905, 285156, 335045, 389376, 452673, 521284, 600301, 685584, 782825, 887364, 1005525, 1132096, 1274065, 1425636
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OFFSET
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1,1
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LINKS
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FORMULA
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Empirical: a(n) = 2*a(n-1) + 2*a(n-2) - 6*a(n-3) + 6*a(n-5) - 2*a(n-6) - 2*a(n-7) + a(n-8) for n>11.
Empirical for n mod 2 = 0: a(n) = n^4 + 10*n^3 + 182*n^2 + 802*n + 6205 for n>3.
Empirical for n mod 2 = 1: a(n) = n^4 + 10*n^3 + 181*n^2 + 780*n + 6084 for n>3.
Empirical g.f.: x*(94249 - 137310*x - 270710*x^2 + 436011*x^3 + 256742*x^4 - 482695*x^5 - 87878*x^6 + 207141*x^7 + 17437*x^8 - 23035*x^9 - 9760*x^10) / ((1 - x)^5*(1 + x)^3). - Colin Barker, Dec 23 2018
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EXAMPLE
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Some solutions for n=4:
..1..1..1..0..1..0..0..0....1..0..0..0..0..0..0..0....1..1..1..0..0..0..0..0
..1..1..1..1..1..1..1..1....1..0..1..0..1..0..0..0....1..1..0..1..0..1..0..1
..1..1..1..1..1..1..1..1....0..1..0..1..0..1..0..1....1..0..1..0..1..0..1..0
..1..1..1..1..1..1..1..1....1..0..1..0..1..0..1..1....1..1..0..1..0..1..0..1
..0..0..1..1..1..1..1..1....0..1..0..1..0..1..1..1....1..0..1..0..1..0..1..1
..0..0..0..1..1..1..1..1....0..0..1..0..1..0..1..1....0..0..0..1..0..1..1..1
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CROSSREFS
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KEYWORD
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nonn
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AUTHOR
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STATUS
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approved
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