The On-Line Encyclopedia of Integer Sequences (OEIS)

Revision History for A187221 (Bold, blue-underlined text is an addition; faded, red-underlined text is a ~~deletion~~.)
Showing entries 1-10 | older changes

A187221

First differences of A187220.
(history; published version)

#18 by N. J. A. Sloane at Wed Feb 24 02:48:19 EST 2021

LINKS

David Applegate, Omar E. Pol and N. J. A. Sloane, <a href="http://neilsloane.com/docA000695/tootha000695_1.pdf">The Toothpick Sequence and Other Sequences from Cellular Automata</a>, Congressus Numerantium, Vol. 206 (2010), 157-191. [There is a typo in Theorem 6: (13) should read u(n) = 4.3^(wt(n-1)-1) for n >= 2.]

Discussion

Wed Feb 24

02:48

OEIS Server: https://oeis.org/edit/global/2889

#17 by N. J. A. Sloane at Tue Nov 27 18:35:51 EST 2018

LINKS

David Applegate, Omar E. Pol and N. J. A. Sloane, <a href="http://neilsloane.com/doc/tooth.pdf">The Toothpick Sequence and Other Sequences from Cellular Automata</a>, Congressus Numerantium, Vol. 206 (2010), 157-191. [There is a typo in Theorem 6: (13) should read u(n) = 4.3^(wt(n-1)-1) for n >= 2.]

Discussion

Tue Nov 27

18:35

OEIS Server: https://oeis.org/edit/global/2774

#16 by N. J. A. Sloane at Thu Jan 21 17:49:26 EST 2016

STATUS

editing

approved

#15 by N. J. A. Sloane at Thu Jan 21 17:49:23 EST 2016

LINKS

David Applegate, <a href="/A139250/a139250.anim.html">The movie version</a>

STATUS

approved

editing

#14 by Charles R Greathouse IV at Sat Sep 26 01:17:12 EDT 2015

LINKS

N. J. A. Sloane, <a href="http://neilsloane.com/docwiki/toothlist.htmlCatalog_of_Toothpick_and_CA_Sequences_in_OEIS">Catalog of Toothpick and Cellular Automata Sequences in the OEIS</a>

Discussion

Sat Sep 26

01:17

OEIS Server: https://oeis.org/edit/global/2460

#13 by Charles R Greathouse IV at Thu Oct 04 10:29:18 EDT 2012

LINKS

David Applegate, Omar E. Pol and N. J. A. Sloane, <a href="http://www.research.attneilsloane.com/~njas/doc/tooth.pdf">The Toothpick Sequence and Other Sequences from Cellular Automata</a>

N. J. A. Sloane, <a href="http://www.research.attneilsloane.com/~njas/doc/toothlist.html">Catalog of Toothpick and Cellular Automata Sequences in the OEIS</a>

Discussion

Thu Oct 04

10:29

OEIS Server: https://oeis.org/edit/global/1833

#12 by Russ Cox at Fri Mar 30 17:34:05 EDT 2012

AUTHOR

_Omar E. Pol (info(AT)polprimos.com), _, Mar 07 2011, Mar 09 2011

Discussion

Fri Mar 30

17:34

OEIS Server: https://oeis.org/edit/global/157

#11 by T. D. Noe at Mon Mar 21 15:15:07 EDT 2011

STATUS

proposed

approved

#10 by Omar E. Pol at Tue Mar 15 17:32:22 EDT 2011

COMMENTS

Number of gulls (or G-toothpicks (or "gulls") added at n-th stage to the gullwing structure of A187220.

#9 by Omar E. Pol at Fri Mar 11 08:46:40 EST 2011

COMMENTS

Apparently this is the connection between A147582 and A139251. - Omar E. Pol, Mar 11 2011

CROSSREFS

Cf. A139250, A139251, A147582, A187211, A187220.