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# Talk:Main Page

## Making the "Main Page" more attractive

I think the different welcome pages of the web site should be made more attractive, a little bit in the spirit of Wikipedia's home page http://en.wikipedia.org/wiki/Main_Page and/or community portal; say, in 2-column format, with

• one box for searching the wiki
• one box with "sequence of the day" (might be just an "include" or extract of an existing sequence : definition, terms, first comment) -- or, why not, a random sequence.
• one box for searching the classical OEIS ("AT&T search engine") - b.t.w. I suggest that there should always be a second button next to the search field for doing that search.
• one box with some "Community" links.

Of course, any other suggestions are welcome. — M. F. Hasler 00:42, 16 October 2010 (UTC)

I've created {{Sequence of the Day/today}} showing today's SOTD if it exists and a July 4 placeholder otherwise, I'll add it as example below this line. It could be inserted at the begin of a line at the end of the main page and/or about page. It could be modified to use the local date of users instead of the current date of this Wiki if desired.
Frank Ellermann 20:20, 20 April 2011 (UTC)
Thanks, that's great!
(please see the next subsection (auto-created by the template) for this proposal and related discussion)M. F. Hasler 12:50, 4 February 2013 (UTC)

#### Gentle reminder

Unfortunately, my above proposal has not earned much success in almost 2.5 years, but maybe the time was not yet ready; things (i.e., this wiki) have changed a lot, since. [The following text is a revised version of my today's post to the oeis-editors list.] I suggest once again that the oeis.org/wiki main/welcome page should be made more attractive, to help, attract and encourage newcomers to either browse the wiki and/or find the concrete information they might be looking for.
I suggest a two-column layout, maybe with 2-3 "boxes" in each column, a bit like http://en.wikipedia.org
The links given might still be the same than those present right now, but they could be grouped by subject and be preceded/followed/"texted" [linked text] with a few words giving more hints on the contents, e.g., in a simplest approach, just some key words/phrases from the content of the concerned page.
I assume that for some of our most prolific wiki contributors, it would not take that much time to propose either an empty canvas of that type, or a pre-filled proposition for such a page.
Would you be so kind as to paste below links to your own proposals for a more attractive main page? -- Thank you! M. F. Hasler 12:50, 4 February 2013 (UTC)

#### Proposals

PS: as suggested by others & written elsewhere, I think it might be a good idea to give due credit for such particular achievements to the respective author on the bottom of the page (e.g., < p align=right >Layout & contents of his welcome page first proposed by SoAndSo< /p >). — M. F. Hasler 12:50, 4 February 2013 (UTC)
[talk]

## Sequence of the Day for March 10

A132995: $a(n) = \gcd\left(\sum_{k = 1}^n p(k), \prod_{j = 1}^n p(j)\right)$, where p(k) is the k-th prime.

{ 2, 1, 10, 1, 14, 1, 2, 77, 10, 3, 10, ..., 2014, 3, 14, ... }

That is, A132995(n) = GCD(A007504(n), A002110(n)).

It may be astonishing that the GCD of sum (A007504) and product (A002110) of the first n primes displays such irregular behaviour. But some of the patterns find easy explanations:

• Every second term ($n = 2, 4, 6, \ldots$) of the sum A007504(n) is odd, so a(2k) cannot be even. It turns out that a(2k) is often (but not always) equal to 1, for small $k = 1, \ldots, 7$, then often equal to 3, for $k = 5, \ldots, 23$.
• Similarly, A007504(n) is even for odd $n = 2k - 1 = 1, 3, 5, 7, \ldots,$ therefore a(2k − 1) is also always even.
• Taking the GCD with the product A002110(n) amounts to have a(n) equal to the product of all those among the first n primes that divide the sum A007504(n).
• For larger terms, it is increasingly probable that A007504(n) has several of the smaller primes as factors. But looking at the very interesting graph of the sequence, it seems that there are infinitely many a(n) = 1, a(n) = 2 and a(n) = 3.

### Trivia

This is the only sequence which has the terms "3, 10" and later "2014", within the displayed 3 lines of data. (It would have been a nice choice for this year's March 14, too, since the 2014 is followed by 3, 14! But there is already another Sequence_of_the_Day_for_March_14 related to π = 3.14...)

A search for "3, 10, __, 2012" yields A212068 and "3, 10, __, 2015" yields A202339 as only result, while no result is found for 2010, 2011, 2013.

What you see above might be February 29 as placeholder for a missing sequence of the day. The older placeholder July 4 did not work very well after it was retired. The proposal is of course to add {{Sequence of the Day/today}} somewhere on the protected main page. –Frank Ellermann 10:35, 5 August 2011 (UTC)
Thank you very much Frank for all your nice work on this. If I had realized this sooner, I would have changed over to your template instead of trying to remember to manually change it at 8 or 9 PM my local time.
However, may I suggest February 30 as the placeholder? February 29 is an actual date on next year's calendar. Alonso del Arte 16:35, 5 August 2011 (UTC)
What I miss most after I destroyed my en:Wikipedia account in 2006 was its intricate template magic, but fortunately this works in all MediaWiki projects ;-) The today-magic is rather harmless, just edit it for any better default, e.g,., German users might like May 32 (featured in a book written by Erich Kästner). If at all it should use an existing OEIS example — the A789654 in SotD drafts spooked me, I replaced it by A123456 for July 4. –Frank Ellermann 00:33, 7 August 2011 (UTC)
{{Sequence of the Day for February 30}} might be popular in Sweden with their 1712-02-30 oddity. –Frank Ellermann 07:44, 9 August 2011 (UTC)

## Looking up a sequence or an A-number should be done at http://oeis.org/, not in the search boxes on this page!

After looking up a sequence or an A-number at http://oeis.org/, one should look up a sequence or an A-number at http://oeis.org/wiki/ to see what comes up, since I've been including the sequences and A-numbers whenever possible in the wiki pages, e.g. try the wiki searches

A001244 or 0, 1, 502, 47840, 2203488, 66318474, 1505621508, 27971176092, 447538817472

Daniel Forgues 02:03, 27 November 2010 (UTC)

## Making the "Main Page" editable in draft mode?

If the "Main Page" was editable (in draft mode) it would allow the Wiki contributors to work on the presentation of the "Main Page"... — Daniel Forgues 03:20, 25 December 2010 (UTC)

Good idea, full protection is rather pointless with the simpler "approval" feature. But who actually is responsible for technical MediaWiki issues here? Just being an admin or "bureaucrat" wouldn't cut it if PHP variables have to be modified, but AFAIK "bureaucrats" can modify page protection. –Frank Ellermann 02:07, 16 August 2011 (UTC)
Seems to be done since July 2011. Actually, on another instance, I learned that this (which is the case with many pages) is usually not intended but an obsolete artifact from the olden days when contents of the wiki were "daily"(?) overwritten with the (then) official contents from OEIS.org. — M. F. Hasler 19:16, 17 February 2013 (UTC)

### Main Page/Prototype

I created the subpage Main Page/Prototype where I proposed a presentation prototype for the Main Page. — Daniel Forgues 16:20, 16 August 2011 (UTC)

I had missed this post when I wrote my above "gentle reminder" including the link to my proposal, User:M. F. Hasler/Proposal for MainPage. — M. F. Hasler 19:09, 17 February 2013 (UTC)

## Adding a link to the "Features/Wishlist" page on the Main page

This page seems a logical complement to the other pages already present (such as Deleted sequences and Wiki Style Sheet). — Olivier Gérard 06:22, 30 March 2011 (UTC)

## Semantic MediaWiki (Semantic Bundle)

I believe that this Wiki would benefit from using the Semantic MediaWiki extension as well as various other related extensions.

My recommendation is to install the Semantic Bundle.

Some of the benefits of using these extensions are:

1. Storing the data in a structured format
2. Enter data in HTML Forms that store the data in a structured format (via Templates that embed semantic annotations)
3. Querying (inner and outer joins) of the data on the wiki can be done either via wikitext or third-party services
4. Exporting data to other formats is simplified greatly
5. Importing data onto the system would be simplified (we could migrate all of the old OEIS onto the system quickly)
6. Allows for creation of task management system to make it easier to manage collaborations amongst a small community

I would be more than happy to provide examples or more explanation for anybody interested in learning more about Semantic MediaWiki and related extensions. I think that this site could hugely benefit from its use. — Joshua Gay 20:55, 11 August 2010 (UTC)

Semantic MediaWiki seems to offer the potential for really sophisticated search queries for sequences! — Daniel Forgues 21:48, 11 August 2010 (UTC)
Check also: http://www.mediawiki.org/wiki/Extension:Semantic_MediaWikiDaniel Forgues 20:53, 20 August 2010 (UTC)

A dicussion about a mistake in Recaman's sequence was moved to the new Talk:Recamán's sequence page.Frank Ellermann 10:48, 16 September 2011 (UTC)