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A252404
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Number of (n+2)X(5+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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2689, 2489, 7425, 21819, 73925, 249530, 762761, 2632409, 8914507, 27372795, 94998346, 322904419, 993656452, 3455998240, 11770408787, 36264169184, 126262279153, 430441032877, 1326978762037, 4622666039941, 15766722542299
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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) = 65*a(n-3) -1346*a(n-6) +14351*a(n-9) -132847*a(n-12) +835969*a(n-15) -4209768*a(n-18) +15460044*a(n-21) -39702866*a(n-24) +78620670*a(n-27) -89680096*a(n-30) -17754183*a(n-33) +155129092*a(n-36) -76681288*a(n-39) -94771951*a(n-42) +63825249*a(n-45) +45921910*a(n-48) -45180122*a(n-51) -698090*a(n-54) +12346433*a(n-57) -3239461*a(n-60) -160991*a(n-63) +116821*a(n-66) -61167*a(n-69) +2548*a(n-72) +968*a(n-75) +56*a(n-78) +2*a(n-81) -a(n-84) for n>87
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EXAMPLE
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Some solutions for n=4
..3..2..2..3..2..2..0....0..2..2..0..2..2..3....2..3..2..2..3..2..2
..3..1..3..3..1..3..3....2..3..2..2..3..2..2....3..0..1..3..3..1..0
..2..2..0..2..2..3..2....3..3..1..3..0..1..3....3..2..2..3..2..2..3
..3..2..2..3..2..2..3....3..2..2..3..2..2..3....2..3..2..2..3..2..2
..3..1..3..3..1..3..3....2..0..2..2..3..2..2....3..3..1..3..0..1..3
..2..2..3..2..2..3..2....3..3..1..0..3..1..3....0..2..2..3..2..2..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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