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A252400
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Number of (n+2)X(1+2) 0..3 arrays with every 3X3 subblock row and diagonal sum equal to 2 3 4 6 or 7 and every 3X3 column and antidiagonal sum not equal to 2 3 4 6 or 7
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1
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458, 293, 319, 426, 631, 964, 1529, 2517, 4097, 6733, 11338, 18763, 31112, 52651, 87448, 145315, 246213, 409305, 680501, 1153412, 1918155, 3189604, 5407047, 8994424, 14957867, 25359593, 42194737, 70176577, 118990108, 198028549
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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) = 11*a(n-3) -39*a(n-6) +55*a(n-9) -59*a(n-12) +40*a(n-15) -10*a(n-18) +2*a(n-21) +a(n-24) for n>28
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EXAMPLE
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Some solutions for n=4
..0..1..3....1..3..3....2..2..3....0..0..2....2..2..3....3..2..2....3..1..3
..2..2..0....2..3..2....1..3..3....2..0..0....1..3..0....3..1..0....0..0..2
..3..2..2....2..2..0....2..0..2....3..0..3....2..3..2....2..2..3....2..0..0
..3..1..3....1..3..3....2..2..3....0..0..2....2..2..3....3..2..2....3..0..3
..2..2..0....2..0..2....1..3..3....2..0..0....1..0..3....3..1..3....0..0..2
..0..2..2....2..2..3....2..0..2....3..1..3....2..3..2....2..2..0....2..0..0
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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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