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A251773
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Number of (n+2) X (2+2) 0..3 arrays with every 3 X 3 subblock row and column sum 3 or 6 and every diagonal and antidiagonal sum not 3 or 6.
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1
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1142, 4182, 12242, 34934, 132886, 430730, 1317638, 5134774, 17297338, 54845894, 214950374, 737930314, 2379309302, 9343006742, 32366662250, 105198487910, 413404292870, 1438370382314, 4692860538998, 18447924909462, 64319132350250
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OFFSET
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1,1
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COMMENTS
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LINKS
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FORMULA
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Empirical: a(n) = a(n-1) +82*a(n-3) -82*a(n-4) -2074*a(n-6) +2074*a(n-7) +19954*a(n-9) -19954*a(n-10) -70907*a(n-12) +70907*a(n-13) -8204*a(n-15) +8204*a(n-16) +575830*a(n-18) -575830*a(n-19) -914592*a(n-21) +914592*a(n-22) -424248*a(n-24) +424248*a(n-25) +1366560*a(n-27) -1366560*a(n-28) -172800*a(n-30) +172800*a(n-31).
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EXAMPLE
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Some solutions for n=4
..0..3..0..0....0..2..1..3....3..2..1..3....0..1..2..0....3..0..3..3
..0..1..2..3....3..1..2..3....0..1..2..0....0..2..1..3....3..1..2..3
..3..2..1..0....0..3..0..0....3..3..0..0....3..3..0..0....0..2..1..0
..0..0..3..3....3..2..1..3....0..2..1..3....3..1..2..3....3..0..3..3
..0..1..2..0....0..1..2..0....3..1..2..3....0..2..1..0....3..1..2..0
..3..2..1..0....0..3..0..3....0..3..3..0....3..3..0..3....0..2..1..3
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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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