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A203358
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Number of n X 4 binary arrays with every 1 immediately preceded by 0 to the left or above.
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1
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5, 61, 565, 5677, 55517, 547897, 5390325, 53087833, 522656405, 5146261573, 50669762053, 498898530085, 4912170264077, 48365462156161, 476208363192837, 4688768398640689, 46165815830098469, 454550623943557645
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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) +42*a(n-2) +54*a(n-3) +23*a(n-4) -7*a(n-5).
Empirical g.f.: x*(5 + 36*x + 50*x^2 + 20*x^3 - 7*x^4) / (1 - 5*x - 42*x^2 - 54*x^3 - 23*x^4 + 7*x^5). - Colin Barker, Jun 04 2018
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EXAMPLE
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Some solutions for n=5:
..0..0..0..0....0..0..0..1....0..1..0..1....0..1..0..1....0..1..0..0
..0..0..0..1....0..1..0..0....1..0..0..1....0..1..1..0....0..1..1..0
..1..1..1..0....0..0..0..1....0..1..1..0....0..1..0..0....1..0..1..1
..0..1..0..0....0..0..0..0....0..0..0..1....1..0..0..1....0..0..0..1
..1..0..0..1....0..0..0..1....0..0..1..0....0..0..1..0....0..1..0..1
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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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