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A251815
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Number of (n+2)X(4+2) 0..2 arrays with every row, column, diagonal or antidiagonal in each 3X3 subblock summing to a prime
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1
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1215, 1511, 5401, 22922, 96649, 409196, 1741500, 7424379, 31630192, 134638409, 573239769, 2441382476, 10396957545, 44272817726, 188528190560, 802834481337, 3418801560572, 14558580766123, 61996115520891, 264004067912028
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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) +6*a(n-2) +21*a(n-3) +53*a(n-4) +32*a(n-5) -61*a(n-6) -245*a(n-7) -323*a(n-8) +337*a(n-9) +944*a(n-10) +125*a(n-11) -1087*a(n-12) -852*a(n-13) +494*a(n-14) +889*a(n-15) +81*a(n-16) -280*a(n-17) -101*a(n-18) -17*a(n-19) -51*a(n-20) -9*a(n-21) +28*a(n-22) +a(n-23) +12*a(n-24) +7*a(n-25) -4*a(n-26) for n>28
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EXAMPLE
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Some solutions for n=4
..1..1..1..1..1..0....1..0..1..1..1..0....1..0..1..1..1..1....1..0..1..1..1..1
..1..1..1..0..1..1....1..1..1..1..1..1....1..1..1..0..1..1....1..1..1..1..1..1
..1..0..1..1..1..1....1..1..1..1..1..1....1..1..1..1..1..1....1..1..1..1..1..1
..1..1..1..1..1..1....1..1..1..1..1..1....0..1..1..1..0..1....1..1..0..1..1..1
..1..1..1..1..1..1....0..1..1..1..1..0....1..1..1..1..1..1....1..1..1..1..0..1
..1..1..1..1..1..0....1..0..1..1..0..1....1..0..1..1..1..0....1..0..1..1..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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