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A224645
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Number of (n+2)X4 0..1 matrices with each 3X3 subblock having the same population
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1
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1280, 2688, 5696, 12320, 31232, 80160, 209216, 587424, 1660544, 4729760, 13842944, 40629408, 119599040, 355446048, 1057577216, 3150294560, 9416112512, 28157621280, 84241395776, 252347085984, 756062793344, 2265711086240
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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) = 4*a(n-1) -3*a(n-2) +36*a(n-3) -144*a(n-4) +108*a(n-5) -503*a(n-6) +2012*a(n-7) -1509*a(n-8) +3480*a(n-9) -13920*a(n-10) +10440*a(n-11) -12564*a(n-12) +50256*a(n-13) -37692*a(n-14) +22464*a(n-15) -89856*a(n-16) +67392*a(n-17) -15552*a(n-18) +62208*a(n-19) -46656*a(n-20)
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EXAMPLE
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Some solutions for n=2
..0..0..0..1....0..0..1..1....0..0..1..0....0..1..0..0....0..0..1..0
..1..0..0..0....0..1..1..0....0..1..0..0....1..0..0..0....0..0..1..0
..1..0..1..1....1..0..1..0....1..1..0..1....0..1..0..1....0..0..1..0
..0..0..0..1....0..0..1..1....1..0..0..1....1..0..0..1....0..1..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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