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• We are very happy to announce that starting May 5 2025,Sean Irvine is the Managing Editor of the OEIS. — Russ Cox, President, OEIS Foundation and N. J. A. Sloane, Chairman, OEIS Foundation.

• This Wiki contains a great many pages of information about the OEIS--everything except the sequences themselves. Seebelow.

• Sadly, it appears that Olivier Gerard, the moderator of the three OEIS mailing lists (SeqFans, Associate-Eds, and Eds-in-Chief) passed away in September 2024. This is a great loss, Olivier was an Editor-in-Chief of the OEIS and founded these mailing lists and moderated them for decades.

• To replace the three lists we have set up two Google Groups. The main one is a Google Group called SeqFan, URLhttps://groups.google.com/g/seqfan, email address[email protected]. This will replace both the old Seq Fan list and the Associate-Eds list. It will discuss interesting sequences, especially open problems, matters concerning the OEIS database and the website, announcements, etc. The archives of the SeqFan Google Group are viewable by anyone on the web.

• To join the new group, if you were a member of the old groups or are a potential new member:
  1. Sign into Google.
  2. Go tohttps://groups.google.com/g/seqfan,
  3. Click "Join this group".
  4. Wait for Robert C. Lyons or me to approve your request. We are in the New York time zone.

• If you don't have a Gmail address, you can still join the group; see the Join a group without a Gmail address section of the following page for instructions:https://support.google.com/groups/answer/1067205

• The second new group is a very small group restricted to OEIS Editors-in-Chief: URLhttps://groups.google.com/g/oeis-eic, email:[email protected]. We have already invited all the Eds-in-Chief to join it. The archives of the OEIS-EiC Google Group are viewable by only the members of the group.

• We have not been able to recover the names of the people on the old list, so if you know someone who is not on the new list, please point them to this announcement.

• Posted by Robert C. Lyons and Neil J. A. Sloane, Oct 18 2024

• Important: The main OEIS lookup page ishttps://oeis.org. Use that page for looking up a sequence, searching the database, contributing new sequences, editing sequences, etc.
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• Videos about OEIS byNeil Sloane:Numberphile videos on YouTube with Brady Haran, 2018-present:
  • Planing Sequences (Le Rabot);A Sequence with a Mistake;Eureka Sequences;The Levine Sequence
  • The Brussels Choice;Dungeon Numbers;(extra);Podcast: The Number Collector
  • Amazing Graphs (I);(II);(III);Don't Know (the Van Eck Sequence);Peaceable Queens
  • How many ways can circles overlap?;The Trapped Knight;Terrific Toothpick Patterns
  • What Number Comes Next?;Primes on the Moon (Lunar Arithmetic)
• Other talks about OEIS byNeil Sloane:
  • Exciting Number Sequences, Rutgers Day, 2021;Richard Guy and the OEIS: A Fifty-Year Friendship, Calgary 2021
  • Conant's Gasket, etc., Rutgers Experimental Math Seminar, 2020;Art and Sequences, Rutgers 2020
  • Old and New Problems from 55 Years of the OEIS,slides, Rutgers EM Seminar, 2019;Coordination Sequences, Planing Numbers, etc.,Part 1,2,Slides, Rutgers EM Seminar, 2019
  • Three (No, 8) Lovely Problems from the OEIS,Part 1,2,Slides, Rutgers EM Seminar, 2017;Confessions of a Sequence Addict, AofA 2017, Princeton;Winter Fruits: New Problems ...,Part 1,2,Slides, Rutgers EM Seminar 2017
  • The OEIS, Mathematical Discovery, and Insomnia, London Ontario, 2016;Open Problems in the OEIS, Rutgers, 2016
  • Unsolved Number Theory Sequences from Alekseyev, Meiburg, Resta, van der Poorten, and Pablo Picasso,Part 1,2, Rutgers EM Seminar, 2015;The Online Encyclopedia of Integer Sequences, Good Ideas in Teaching Precalculus, Rutgers 2015;On the No. of ON Cells in Cellular Automata,Part 1,2, Rutgers EM Seminar, 2015;Interview by Marc Chamberland, JMM 2015
  • The OEIS Today: The Major Problems, DIMACS Conference to celebrate the 50th birthday of the OEIS, reaching 250,000 sequences, and Neil Sloane's 75th birthday, 2014;Error-Correcting Codes, Group Theory, and Invariant Theory,1,2, Rutgers 2014
  • 2178 And All That,Part 1,2, Rutgers EM Seminar, 2013;On Curling Numbers ..., Toronto, 2013;The On-Line Encyclopedia of Integer Sequences: The First 100 Years,Part 1,2, Rutgers EM Seminar, 2013
  • The On-Line Encyclopedia of Integer Sequences, Rutgers University, Feb. 2012.
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• Integer Sequences K-12 Conference, 2015;Talks at OEIS 50 Workshop, 2014;Suggestions from OEIS 50 Workshop;The 2004 OEIS 100K E-Party
• John Riordan Prize of $1000 for the best solution to an open problem in the OEIS in 2015.

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