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A302377
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Number of nX4 0..1 arrays with every element equal to 1, 2, 3 or 4 horizontally, diagonally or antidiagonally adjacent elements, with upper left element zero.
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1
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2, 46, 430, 4640, 48980, 514655, 5421003, 57068484, 600825641, 6325616349, 66596986535, 701143904697, 7381754599676, 77716287676023, 818209464051271, 8614239598434833, 90692087070581459, 954820743332757828
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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) = 8*a(n-1) +33*a(n-2) -25*a(n-3) -427*a(n-4) -361*a(n-5) +1618*a(n-6) +3070*a(n-7) -2572*a(n-8) -6300*a(n-9) +3216*a(n-10) +3053*a(n-11) -8191*a(n-12) +955*a(n-13) +12197*a(n-14) -2105*a(n-15) +634*a(n-16) -1833*a(n-17) -1727*a(n-18) -2285*a(n-19) +2346*a(n-20) -1596*a(n-21) +780*a(n-22) -134*a(n-23) -6*a(n-24) +44*a(n-25) -16*a(n-26)
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EXAMPLE
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Some solutions for n=5
..0..0..0..0. .0..0..0..0. .0..1..1..0. .0..0..0..0. .0..1..1..0
..1..1..0..1. .0..1..1..0. .1..0..0..1. .1..1..0..0. .0..0..0..1
..1..1..1..0. .0..0..1..1. .0..1..0..1. .0..1..0..0. .1..1..1..1
..0..0..1..1. .0..0..1..0. .0..0..1..1. .1..0..1..0. .0..1..1..0
..0..1..0..0. .1..1..0..0. .1..1..0..0. .0..1..1..1. .0..0..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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