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A252251
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Number of (n+2) X (5+2) 0..3 arrays with every 3 X 3 subblock row and column sum not equal to 0 3 5 6 or 7 and every 3 X 3 diagonal and antidiagonal sum equal to 0 3 5 6 or 7.
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1
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463, 302, 279, 297, 327, 366, 414, 492, 594, 720, 924, 1191, 1521, 2055, 2754, 3618, 5016, 6846, 9108, 12768, 17559, 23481, 33063, 45606, 61110, 86196, 119034, 159624, 225300, 311271, 417537, 589479, 814554, 1092762, 1542912, 2132166, 2860524
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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) = a(n-1) + 3*a(n-3) - 3*a(n-4) - a(n-6) + a(n-7) for n>9.
Empirical g.f.: x*(463 - 161*x - 23*x^2 - 1371*x^3 + 513*x^4 + 108*x^5 + 457*x^6 - 173*x^7 - 38*x^8) / ((1 - x)*(1 - 3*x^3 + x^6)). - Colin Barker, Dec 02 2018
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EXAMPLE
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Some solutions for n=4:
..3..0..1..0..1..0..1....2..2..0..2..2..0..2....0..2..2..0..2..2..0
..3..1..0..1..0..1..0....3..0..1..0..3..1..0....2..3..3..2..3..3..2
..3..0..1..0..1..0..1....3..0..1..0..3..1..0....2..3..3..2..3..3..2
..3..1..0..1..0..1..0....2..2..0..2..2..0..2....0..2..2..0..2..2..0
..3..0..1..0..1..0..1....3..0..1..0..3..1..0....2..3..3..2..3..3..2
..3..1..0..1..0..1..0....3..0..1..0..3..1..0....2..3..3..2..3..3..2
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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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