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A252469
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Number of (n+2)X(4+2) 0..3 arrays with every 3X3 subblock row, column, diagonal and antidiagonal sum not equal to 0 3 5 6 or 8
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1
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2380, 1463, 5367, 22832, 96543, 409090, 1741406, 7424273, 31630086, 134638315, 573239663, 2441382370, 10396957451, 44272817620, 188528190454, 802834481243, 3418801560466, 14558580766017, 61996115520797, 264004067911922
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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) +5*a(n-2) +14*a(n-3) +34*a(n-4) -16*a(n-5) -79*a(n-6) -150*a(n-7) -94*a(n-8) +581*a(n-9) +457*a(n-10) -913*a(n-11) -631*a(n-12) +692*a(n-13) +433*a(n-14) -236*a(n-15) -116*a(n-16) +72*a(n-17) -57*a(n-18) -32*a(n-19) +38*a(n-20) -15*a(n-21) +5*a(n-22) +11*a(n-23) -4*a(n-24) for n>28
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EXAMPLE
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Some solutions for n=4
..3..1..3..3..1..3....1..3..3..3..3..3....3..3..3..3..3..3....3..3..3..3..3..1
..3..3..3..3..3..3....3..3..1..3..3..3....3..3..3..3..3..1....3..3..3..1..3..3
..1..3..3..3..3..3....3..3..3..3..3..3....3..3..3..3..3..3....3..3..3..3..3..3
..3..3..3..3..3..1....3..3..3..3..3..3....1..3..3..3..3..3....3..3..3..3..3..3
..3..3..3..3..3..3....1..3..3..3..3..3....3..3..3..3..3..1....3..3..1..3..3..1
..3..3..3..3..3..3....3..3..3..1..3..3....3..3..3..1..3..3....1..3..3..3..1..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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