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A163714
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Number of nX2 binary arrays with all 1s connected, a path of 1s from top row to bottom row, and no 1 having more than two 1s adjacent
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3
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3, 7, 10, 16, 26, 42, 68, 110, 178, 288, 466, 754, 1220, 1974, 3194, 5168, 8362, 13530, 21892, 35422, 57314, 92736, 150050, 242786, 392836, 635622, 1028458, 1664080, 2692538, 4356618, 7049156, 11405774, 18454930, 29860704, 48315634, 78176338
(list; graph; refs; listen; history; internal format)
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OFFSET
| 1,1
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COMMENTS
| Same recurrence for A163695
Same recurrence for A163733
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LINKS
| R. H. Hardin, Table of n, a(n) for n=1..100
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FORMULA
| Empirical: a(n)=a(n-1)+a(n-2) for n>=5
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EXAMPLE
| All solutions for n=4
...1.0...1.0...1.1...1.1...0.1...0.1...1.1...1.1...1.0...1.1...1.0...1.0...0.1
...1.0...1.0...1.0...1.0...0.1...0.1...0.1...0.1...1.0...1.0...1.1...1.1...0.1
...1.0...1.0...1.0...1.0...0.1...0.1...0.1...0.1...1.1...1.1...0.1...0.1...1.1
...1.0...1.1...1.0...1.1...0.1...1.1...0.1...1.1...0.1...0.1...0.1...1.1...1.0
------
...1.1...0.1...0.1
...0.1...1.1...1.1
...1.1...1.0...1.0
...1.0...1.0...1.1
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CROSSREFS
| Cf. A090991, A078642, A047992. [From R. J. Mathar (mathar(AT)strw.leidenuniv.nl), Aug 06 2009]
Sequence in context: A088636 A114113 A100056 * A128223 A111244 A022120
Adjacent sequences: A163711 A163712 A163713 * A163715 A163716 A163717
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KEYWORD
| nonn
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AUTHOR
| R. H. Hardin (rhhardin(AT)att.net) Aug 03 2009
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