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A252028
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Number of (n+2)X(4+2) 0..2 arrays with every 3X3 subblock row, column, diagonal and antidiagonal sum not equal to 0 2 or 4
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1
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809, 1929, 7182, 29781, 126920, 541544, 2306234, 9836361, 42007667, 179412369, 766247783, 3273106717, 13982899118, 59736693957, 255202401835, 1090262794558, 4657798693225, 19899000968428, 85012294225985, 363188622741325
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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) = 5*a(n-1) -4*a(n-2) +14*a(n-3) -23*a(n-4) -91*a(n-5) -13*a(n-6) -118*a(n-7) +815*a(n-8) +1080*a(n-9) -692*a(n-10) -2103*a(n-11) -5420*a(n-12) +2379*a(n-13) +8473*a(n-14) +4179*a(n-15) +8147*a(n-16) -18588*a(n-17) -30186*a(n-18) +2771*a(n-19) +28308*a(n-20) +32734*a(n-21) +6559*a(n-22) -23299*a(n-23) -16727*a(n-24) -666*a(n-25) +7553*a(n-26) -5973*a(n-27) -14481*a(n-28) +7873*a(n-29) +34754*a(n-30) +25934*a(n-31) -15978*a(n-32) -45920*a(n-33) -43974*a(n-34) -14735*a(n-35) +6402*a(n-36) +15091*a(n-37) +14803*a(n-38) +11460*a(n-39) +9120*a(n-40) +5581*a(n-41) +3303*a(n-42) +1366*a(n-43) +342*a(n-44) +18*a(n-45) -72*a(n-46) for n>50
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EXAMPLE
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Some solutions for n=4
..1..0..2..1..2..2....2..1..2..2..2..2....1..2..2..2..1..2....2..1..2..2..2..1
..0..2..1..2..2..1....2..2..2..2..2..1....2..2..2..2..2..1....1..2..2..2..2..2
..2..1..2..2..1..2....2..2..2..2..2..2....2..2..2..2..2..2....2..2..2..2..1..2
..1..2..2..1..2..2....2..2..2..2..2..2....1..2..2..2..2..2....2..2..2..2..2..2
..2..2..1..2..2..1....1..2..2..2..2..2....2..1..2..2..1..2....2..1..2..2..2..2
..2..1..2..2..1..0....2..2..1..2..2..2....0..2..1..2..2..2....2..2..2..1..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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