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A181247
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Number of n X 4 binary matrices with no 2 X 2 block having four 1's.
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1
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16, 216, 3032, 42176, 587920, 8191392, 114142368, 1590466304, 22161786304, 308805072256, 4302929532288, 59957567962112, 835456401197312, 11641356029819392, 162212139560176128, 2260284639281590272
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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) = 10*a(n-1) + 54*a(n-2) + 16*a(n-3) - 64*a(n-4).
Empirical g.f.: 8*x*(2 + 7*x + x^2 - 8*x^3) / (1 - 10*x - 54*x^2 - 16*x^3 + 64*x^4). - Colin Barker, Mar 26 2018
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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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