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A255797
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Number of (n+2) X (4+2) 0..1 arrays with no 3 x 3 subblock diagonal sum 1 and no antidiagonal sum 2 and no row sum 0 and no column sum 3.
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1
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409, 262, 198, 200, 268, 263, 384, 336, 326, 344, 476, 471, 708, 608, 598, 632, 892, 887, 1356, 1152, 1142, 1208, 1724, 1719, 2652, 2240, 2230, 2360, 3388, 3383, 5244, 4416, 4406, 4664, 6716, 6711, 10428, 8768, 8758, 9272, 13372, 13367, 20796, 17472, 17462
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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) = 3*a(n-6) - 2*a(n-12) for n>15.
Empirical g.f.: x*(409 + 262*x + 198*x^2 + 200*x^3 + 268*x^4 + 263*x^5 - 843*x^6 - 450*x^7 - 268*x^8 - 256*x^9 - 328*x^10 - 318*x^11 + 374*x^12 + 124*x^13 + 16*x^14) / ((1 - x)*(1 + x)*(1 - x + x^2)*(1 + x + x^2)*(1 - 2*x^6)). - Colin Barker, Dec 20 2018
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EXAMPLE
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Some solutions for n=4:
..1..0..0..1..1..1....0..1..0..1..0..1....1..0..0..1..0..0....1..0..0..1..0..1
..0..1..1..0..1..0....0..0..1..0..1..0....0..1..0..0..1..0....0..1..1..0..1..0
..0..1..0..1..0..0....0..1..0..1..0..1....0..0..1..0..0..1....0..1..0..1..0..0
..1..0..1..1..0..0....1..0..1..0..1..0....1..0..0..1..0..0....1..0..1..1..0..0
..0..1..0..0..1..1....0..1..0..1..0..1....0..1..0..0..1..0....0..1..0..0..1..1
..1..0..1..0..1..1....1..1..1..0..1..0....0..0..1..0..0..1....1..0..1..0..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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