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A160121
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First differences of Y-toothpick numbers A160120.
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34
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1, 3, 3, 9, 3, 9, 9, 21, 9, 9, 9, 21, 15, 21, 27, 51, 27, 9, 9, 21, 15, 21, 27, 51, 33, 21, 27, 51, 51, 57, 69, 117, 81, 21, 9, 21, 15, 21, 27, 51, 33, 21, 27, 51, 51, 57, 69, 117, 87, 33, 27, 51, 51, 57, 75, 129, 117, 75, 69, 117, 135, 141, 171, 279, 231, 69, 9, 21, 15, 21, 27
(list; graph; refs; listen; history; internal format)
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OFFSET
| 1,2
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COMMENTS
| Number of Y-toothpicks added to the Y-toothpick structure at the n-th stage.
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LINKS
| David Applegate, Omar E. Pol and N. J. A. Sloane, The Toothpick Sequence and Other Sequences from Cellular Automata
N. J. A. Sloane, Catalog of Toothpick and Cellular Automata Sequences in the OEIS
David Applegate, The movie version
O. E. Pol, Illustration of initial terms of A139251, A160121, A147582 (Overlapping figures) [From Omar E. Pol (info(AT)polprimos.com), Nov 02 2009]
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EXAMPLE
| Contribution from Omar E. Pol (info(AT)polprimos.com), Jun 18 2009: (Start)
May be written as a triangle:
1,
3,
3,
9,
3,9,
9,21,9,9,
9,21,15,21,27,51,27,9,
9,21,15,21,27,51,33,21,27,51,51,57,69,117,81,21,
9,21,15,21,27,51,33,21,27,51,51,57,69,117,87,33,27,51,51,57,75,129,117,75,...
Rows converge to A161326.
(End)
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CROSSREFS
| Y-toothpick sequence: A160120.
Cf. A139251.
Cf. A160171, A160173, A161207, A161329, A161331.
Cf. A161326, A161431. [From Omar E. Pol (info(AT)polprimos.com), Jun 18 2009]
Cf. A147582. [From Omar E. Pol (info(AT)polprimos.com), Nov 02 2009]
Sequence in context: A145444 A165824 A151710 * A048883 A036553 A166466
Adjacent sequences: A160118 A160119 A160120 * A160122 A160123 A160124
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KEYWORD
| nonn
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AUTHOR
| Omar E. Pol (info(AT)polprimos.com), May 02 2009
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EXTENSIONS
| More terms from David Applegate (david(AT)research.att.com), Jun 14 2009
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