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A252058
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Number of (n+2)X(1+2) 0..2 arrays with every 3X3 subblock row, column, diagonal and antidiagonal sum not equal to 1 2 or 4
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1
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125, 200, 383, 843, 1948, 4569, 10836, 25739, 61193, 145794, 347496, 828129, 1973810, 4704512, 11212968, 26726886, 63705038, 151842605, 361924119, 862663872, 2056196252, 4901041429, 11681865518, 27844260428, 66368096889
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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) -a(n-2) +9*a(n-3) -10*a(n-4) +7*a(n-5) -24*a(n-6) +12*a(n-7) -18*a(n-8) +23*a(n-9) +7*a(n-10) +26*a(n-11) -2*a(n-12) -21*a(n-13) -21*a(n-14) -12*a(n-15) +13*a(n-16) +5*a(n-17) +7*a(n-18) -a(n-19) +4*a(n-20) -2*a(n-21) -2*a(n-23) for n>24
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EXAMPLE
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Some solutions for n=4
..2..1..2....2..2..1....1..1..1....2..2..2....1..0..2....2..1..2....1..0..2
..1..2..2....2..2..2....2..2..2....2..2..2....0..2..1....2..2..2....2..1..2
..2..2..2....2..2..2....2..2..2....2..1..2....2..1..2....1..2..2....2..2..1
..2..2..2....1..2..2....2..2..1....2..2..2....1..2..2....2..1..2....1..2..2
..1..2..2....2..2..2....2..2..2....2..2..1....2..2..1....0..2..1....2..2..2
..2..1..2....2..1..2....2..2..2....1..2..2....2..1..2....1..2..2....2..2..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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