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A295092
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Number of nX3 0..1 arrays with each 1 horizontally or vertically adjacent to 1 or 3 1s.
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1
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3, 11, 33, 114, 377, 1249, 4151, 13765, 45704, 151720, 503627, 1671816, 5549529, 18421629, 61150537, 202988906, 673820905, 2236745220, 7424865048, 24646804474, 81814951110, 271584345815, 901522957697, 2992601212814, 9933925633736
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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) = 3*a(n-1) +3*a(n-3) -a(n-4) +11*a(n-5) -5*a(n-6) -14*a(n-8) -4*a(n-9) -9*a(n-10) -a(n-11) +a(n-12) +4*a(n-14) +a(n-16)
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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..0. .1..0..1. .0..0..1. .0..1..0
..1..0..1. .0..0..1. .0..1..0. .1..0..1. .1..0..1. .0..0..1. .1..1..1
..1..0..1. .0..0..1. .1..0..1. .0..1..1. .0..0..0. .0..0..0. .0..0..0
..0..1..0. .0..0..0. .1..0..1. .0..0..1. .1..0..0. .1..1..0. .0..0..1
..0..1..0. .1..1..0. .0..0..0. .1..1..0. .1..0..0. .0..0..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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