Talk:On-Line Encyclopedia of Integer Sequences

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For 2004 talk, see Talk:On-Line Encyclopedia of Integer Sequences/Archive2004.

Contents

[edit] OEIS linking syntax help

I would like to make a page along the lines of "Wikipedia:How to cite the OEIS" and include a link to that from this article. That page would explain the five different ways of citing and linking sequences in the OEIS and illustrate how to accomplish each one. PrimeFan 22:46, 14 July 2005 (UTC)

I've just spent 20 minutes searching for a template, convinced I'd seen one before. I'd welcome a synopsis. Hv 01:07, 17 August 2005 (UTC)
Using Sloane's A012345 as an example, the table below shows the five different ways. PrimeFan 19:32, 18 August 2005 (UTC)
[http://www.research.att.com/projects/OEIS?Anum=A012345] [1]
[http://www.research.att.com/projects/OEIS?Anum=A012345 A012345] A012345
[[OEIS:A012345]] OEIS:A012345
{{OEIS|id=A012345}} (sequence A012345 in OEIS)
{{OEIS2C|id=A012345}} A012345 This format is used for second and subsequent citations in a given article.
I don't think the first two are really worth mentioning, and the third is a maybe - I'd class the templates as generally preferable, both for brevity and for the meta-information provided by having a reference to the template.
My own search turned up nothing via Wikipedia:Template, and I eventually stumbled across the templates in another page.
I certainly wouldn't have guessed what "OEIS2C" stood for, so some explanation somewhere would surely help. I did look in Wikipedia:Template messages/Links, so a reference there would be a start. Hv 02:03, 19 August 2005 (UTC)
I'm not even sure how things are sorted there at Template messages/Links. I'd have to carefully examine that page before I dared add anything to it. PrimeFan 20:39, 22 August 2005 (UTC)

[edit] Make encyclopedic

The current text has a mix of encyclopedic information and some very low-level "how-to" material. It needs to be cleaned up.... --Macrakis 23:31, 26 September 2005 (UTC)

Oh, how easy it is to complain about a problem and not do a thing to fix it! "It needs to be cleaned up," easy to say. "Make encyclopedic," easy it is to give that command.
At any rate, there isn't a problem. What you call "low-level how to" is a much better way to explain a potentially cryptic mathematical topic. A professional mathematician is given to saying things like "It is obvious that \int_{-N}^{N} \sqrt{k\pi\lambda}\, dx hence k = x2μ." The lexicographic order of the OEIS is here explained far more clearly than in the OEIS itself! Robert Happelberg 22:06, 27 September 2005 (UTC)
OK, I've started fixing it. --Macrakis 01:51, 28 September 2005 (UTC)
Good job so far, Macrakis. Bob makes a good point, too. With Macrakis's and Bob's help, this article will eventually strike a good balance between spontaneity and professionalism. PrimeFan 15:48, 28 September 2005 (UTC)

[edit] Errors in the database

The article says "For a database of its magnitude, the OEIS is relatively free of errors. ... The more common mistakes in the OEIS occur in fields other than the sequence or signed field."

I have reason to doubt this. In early January 2000 or 2001, I took the database and ran a program on it to look for sequences whose terms were all prime except one. There were something like 100+ of these, perhaps as many as 300 (I can't remember for sure). I started checking these to see if the non-prime term was in error. I think I checked a little over 100 sequences. I found 10 or 11 errors. The errors were about what you would expect:

  1. transpose two digits
  2. spurious digit or digit omitted
  3. repeating the wrong digit, i.e. 355 instead of 335.
  4. leaving a comma in a term with four or more digits, making it appear to be two separate terms
  5. omitting a comma between two terms

So around 10% of the sequences I checked had obvious errors, and there could have been others. Bubba73 (talk), 23:26, 15 January 2006 (UTC)

Then I'm in trouble. For the vast majority of Wikipedia articles I've written about various kinds of numbers (e.g., Carol numbers, prime quadruplets), I've taken the listing from the OEIS. In a few cases I take the listing from Mathematica.
For my part, I will double-check the sequences listed in articles I've written. For your part, could you re-run your "sequences whose terms were all prime except one" search on a more recent copy of the table? PrimeFan 21:05, 17 January 2006 (UTC)

[edit] Self-referential paradox

In the 'Self-referentiality' section, "sequences A053873, n is in An, and A053169, n is not in An" are referred to as "delightfully paradoxical" because "[t]he paradox is, which sequences do 53169 and 53873 belong to?" Surely only 53169 in A053169 gives rise to a paradox?

Sendhil 01:24, 20 July 2006 (UTC)

Alright, prove that 53873 does belong in A053873. Anton Mravcek 16:41, 20 July 2006 (UTC)
Or prove that it does not.
And 53169 not in A053169 also gives rise to a paradox --Rumping 19:12, 22 September 2007 (UTC)
Looking at this a year later, I stand by calling these issues "paradoxical." My problem now would be the word "delightfully." I find these paradoxes delightful but that might just be my POV. Some people might find these annoying. Anton Mravcek 20:32, 22 September 2007 (UTC)