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A252070
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Number of (n+2)X(3+2) 0..2 arrays with every 3X3 subblock row, column, diagonal and antidiagonal sum not equal to 0 3 or 4
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1
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183, 419, 1497, 5085, 17455, 60245, 206747, 711749, 2455039, 8451165, 29078125, 100127009, 344830169, 1187280673, 4087598979, 14073866379, 48459148697, 166851565147, 574482172193, 1977991833479, 6810453196661, 23449166058617
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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) = 2*a(n-1) +11*a(n-3) +20*a(n-4) +12*a(n-5) -7*a(n-6) -69*a(n-7) -49*a(n-8) +69*a(n-9) +59*a(n-10) -9*a(n-11) -30*a(n-12) -14*a(n-13) +2*a(n-14) +4*a(n-16) for n>18
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EXAMPLE
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Some solutions for n=4
..2..2..2..2..2....2..1..2..2..2....2..2..2..2..2....2..2..2..2..1
..2..2..2..2..2....1..2..2..2..2....2..2..2..2..2....2..2..2..2..2
..2..2..2..2..2....2..2..2..2..1....2..2..2..2..1....2..2..2..2..2
..2..2..2..2..1....2..2..2..2..2....2..2..2..2..2....1..2..2..2..2
..2..1..2..2..2....2..1..2..2..2....2..1..2..2..2....2..2..2..2..1
..2..2..2..1..2....2..2..2..2..2....2..2..2..2..1....2..2..2..1..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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