Wikipedia:Articles for deletion/Regular number

The following discussion is an archived debate of the proposed deletion of the article below. Please do not modify it. Subsequent comments should be made on the appropriate discussion page (such as the article's talk page or in a deletion review). No further edits should be made to this page.

The result of the discussion was Delete. The evidence is overwhelming that this term is not commonly understood in mathematics. --Tony Sidaway 23:06, 12 July 2006 (UTC)

[edit] Regular number

The article's claim is just false; "regular number" is not a standard name for a number with a terminating decimal expansion. --Trovatore 14:52, 7 July 2006 (UTC)

• Keep - It _does_ appear to be a standard name for such a number. [1] refers. Tevildo 15:40, 7 July 2006 (UTC)+
• Keep per Tevildo. --Emc² (CONTACT ME) 15:57, 7 July 2006 (UTC)
• Keep - I've never heard the term before, but Tevildo's link cites sources quite well enough. PresN 16:06, 7 July 2006 (UTC)
• Comment The link is to Weisstein's encyclopedia. We've had this problem before. Eric propagates silly neologisms and people at WP blindly copy him. Let's nip this one in the bud. --Trovatore 16:49, 7 July 2006 (UTC)
• Delete and forward to decimal expansion. I agree that the terminology is uncommon. Even if it were common, this article could never be more than just a definition; it makes more sense to merge it into a full article. Consider the case of even numbers. CMummert 17:08, 7 July 2006 (UTC)
• Merge and Redirect. Term appears legitimate after a quick google search. I would support merging this to decimal expansion and making the page in question redirect. -- Chet nc _contribs^talk 17:11, 7 July 2006 (UTC)
  • Question did you follow a sample of the Google links to see how many of them ultimately pointed back to Weisstein? --Trovatore 17:18, 7 July 2006 (UTC)
• Delete. Not a standard term, many google hits are for other meanings. Doesn't seem to be used much outside MathWorld and possibly the one reference given there. JPD (talk) 17:47, 7 July 2006 (UTC)
• Weak deleteKeep: at the moment, this is a dicdef and deletable. I recall a slightly different use of "regular number" for base 60. If this checks out I may vote to keep. Septentrionalis 17:49, 7 July 2006 (UTC)
  • Found it: [2]; also discussed in Conway and Guy, under this term IIRC.
• No vote. I think it would be appropriate to keep this if relevant material from decimal expansion were moved here and linked. Otherwise, it should be merged into it. It should not be deleted, as this is obviously a legitimate search term (it's on Mathworld). Deco 17:56, 7 July 2006 (UTC)
  • Comment why does its presence on Mathworld make it a "legitimate search term"? While Mathworld has its uses, the fact that it has all these articles giving silly definitions for concepts that mathematicians don't find useful or well-motivated is absolutely a bad thing. We should not be compounding Weisstein's offense by repeating him on these. (By the way, Weisstein is not even a mathematician; he's an astronomer.) --Trovatore 18:02, 7 July 2006 (UTC)
    • Comment Do you have the same low opinion of Thabit ibn Qurra? Anton Mravcek 22:21, 7 July 2006 (UTC)
    • Semi-barbed attack: Yeah, Trovatore, do you hate ALL astronomers!?? What are you insinuating??? That if Thabit ibn Qurra wrote an online math resource, you would similarly bash it? Or that you think online math resources should have someone with significant math training involved in the editorial process? Ridiculous! Go home. --Chan-Ho (Talk) 12:30, 8 July 2006 (UTC)
• Delete Inconsistent with regular prime and normal number. Definition is just a base 10 analog of dyadic rational so could perhaps be better called 10-adic rational. DRLB 18:30, 7 July 2006 (UTC)
• Strong delete not a useful definition, and I don't believe it is in widespread use apart from Mathworld readers. At the most, mention the concept somewhere else, but certainly not worth its own article. Madmath789 18:32, 7 July 2006 (UTC)
• Delete. In more than forty years of doing mathematics I've never encountered this terminology. Mathworld is a useful source, but is also known for not being reliable. --Lambiam^Talk 19:16, 7 July 2006 (UTC)
• Delete per nom. -lethe ^{talk +} 19:43, 7 July 2006 (UTC)
• Comment If the article is rewritten to generalize to other bases, I'll vote keep. I'm not voting today. PrimeFan 20:27, 7 July 2006 (UTC)
• Delete per Trovatore. Dmharvey 22:16, 7 July 2006 (UTC)
• Merge and redirect Anton Mravcek 22:21, 7 July 2006 (UTC)
• Comment When I first saw this, I was a bit confused: I was thinking of regular prime. Maybe other people will make the same mistake I did, and an explantory note would be nice. Then again, maybe I'm out to Lunch 23:05, 7 July 2006 (UTC)
• Delete per Trovatore. --KSmrq^T 23:37, 7 July 2006 (UTC)
• K33p. This is CLEARLY a standard math term. No researcher uses it, e.g. no relevant hits on MathSciNet, but IT'S IN MATHWORLD. It shouldn't even matter what sources MathWorld cites, or if they cite anything!!! We're talking about MATHWORLD here. And for those of you trying to smear MATHWORLD, let me point out that it is NOT a "self-published resource". The ONLINE version may be run by Wolfram who employs Eric Weisstein, editor in chief, and Weisstein himself writes many of the entries, but CRC PRESS, a fully independent entity and publisher, publishes the book form. Take that, Trovatore! Finally, we have [3]:

  MathWorld continues to grow and evolve with the assistance of thousands of contributors. Careful oversight of all aspects of its content and interface by creator Eric Weisstein, and more recently with able assistance from MathWorld associate Ed Pegg, Jr., provides an exacting level of quality, accuracy, and consistency. As a result, MathWorld is considered not only the clearest and most readable online resource for mathematics, but also one of the most reliable.

  What's your beef, Trovatore? Envy, perhaps? --Chan-Ho (Talk) 12:30, 8 July 2006 (UTC)
  • Response Chan-Ho, does someone have your password? I have trouble believing you'd write the above, with an edit summary in leet of all things. Everyone, please note that the source for the claim that MathWorld is considered reliable is—wait for it—MathWorld. --Trovatore 16:28, 8 July 2006 (UTC)

    Indeed, this immoderate post is strikingly inconsistent with the history of posts by Chan-Ho. --KSmrq^T 04:39, 9 July 2006 (UTC)

    • On reflection, it's probably satire. Asking me if I'd object to an online math service written by a 9th-century astronomer should have been a clue. I just didn't get the joke the first time around. --Trovatore 04:59, 9 July 2006 (UTC)
• This is certainly not a common usage in mathematics, as a bit of Googling for "regular number" shows. I've also not heard this term used in many years of mathematical experience; what this article describes is most commonly called a "finite decimal" or "finite decimal expansion"; the MathWorld article also acknowledges this use as valid. Merge into decimal representation and delete the redirect from "regular number" unless other supporting references for this usage can be provided from independent sources. (Mirrors of Wikipedia and sources that cite MathWorld as their sole support don't count for this purpose.) -- The Anome 12:38, 8 July 2006 (UTC)
• Merge and Redirect. Giftlite 15:40, 8 July 2006 (UTC)
• Delete. The term isn't in common use outside MathWorld, and this may not even be the most common use of the term outside MathWorld. — Arthur Rubin | (talk) 00:18, 9 July 2006 (UTC)
• Comment Following Septentrionalis' findings above, I came across this document on Mesopotamian maths (it's a PDF), that goes into more detail about "regular numbers" in its 2nd section (page 1). Importantly, the article generalises the definition of "regular numbers" beyond base 10 (whereas Mathworld talks only about decimals). If this WP article is to be kept, it would appear to me that the right thing to do would be to generalise the WP definition the same way for any base, or redirect to the appropriate existing article that does this job, if there is one (i.e., decimal expansion apparently wouldn't fit the bill here). --DaveG12345 03:04, 9 July 2006 (UTC)
• Keep after generalizing to other bases $b$ as suggested by PrimeFan and DaveG12345. CompositeFan 22:39, 9 July 2006 (UTC)
• Merge into decimal representation. No point generalising to other bases, as every rational number is "regular" in any base which is a multiple of the prime factors of its denominator, and no irrational number is "regular" in any base, so the generalisation simply duplicates the distinction between rationals and irrationals. Gandalf61 11:19, 10 July 2006 (UTC)
• Comment. We have to avoid generalizations, even if they are easy, unless they are well documented (because original research WP:NOR is not allowed). The paper on Mesopotamian math doesn't even have a reference to who uses the phrase regular number; it seems in that paper that the author is just using the phrase as a bit of local notation to help the exposition. You might think the author is trying to claim that regular number is a well known term, except that it isn't. I think nobody has exhibited a use of regular number as a defined term in a published monograph other than Mathworld. CMummert 13:55, 10 July 2006 (UTC)
• Comment: Here's how it looks to me:
  • The link in the article's history to WP:MEA suggests the article was, in fact, created specifically because a corresponding article existed on MathWorld. The MathWorld article, in turn, cites two entries from the Online Encyclopedia of Integer Sequences, and two books.
    • One OEIS entry (A117920) lists Weisstein as the author.
    • The other (A003592) actually uses the term "terminating decimal". Both OEIS entries refer back to MathWorld.
    • The book Gamma: Exploring Euler's constant is apparently cited to justify the term "finite decimal", and not "regular number", although it is ambiguous. But in fact, Amazon's "Search Inside This Book" feature does not find "regular number" in this book, while it does find "finite decimal" and "(non-)terminating decimal".
      • Checked my copy of Havil's Gamma and I can confirm he does not use the term "regular number". Gandalf61 08:41, 11 July 2006 (UTC)
    • The book Penguin Dictionary of Curious and Interesting Numbers is not cited in the context of the term, but of the interesting integer sequences. (Interesting? Well, if they say so.) Again, "Search Inside This Book" finds "finite decimal" and "(non-)terminating decimal" but not "regular number".
  • The links above to "regular number" above on this AfD seem to be something related, but quite different. In both places, a regular number is an integer of the form 2^a3^b5^c. It does not apply to arbitrary rational (or real) numbers at all, it has to do with ancient mathematical practice. They do not however appear to be local notation, as suggested above, because in fact they both cite:
    • Papers by A. Sachs from the Journal of Cuneiform Studies : "Babylonian mathematical texts I: reciprocals of regular sexagesimal numbers" (1947) and "Babylonian mathematical texts II: approximations of reciprocals of irregular numbers in an Old Babylonian text" (1952). And if this is not the source, then I surmise it is something else in this discipline. I surmise that the mention above of Conway also ultimately refers to these Babylonian techniques, which, I repeat, is a totally different context from the "regular number" of the article as it stands. 192.75.48.150 15:29, 10 July 2006 (UTC)
• Delete: The last extensive comment by 192.75.48.150 has convinced me that the current article is describing a neologism created by Eric Weisstein. At best, we could try and rewrite the article to reflect the perhaps well-known use of "regular number" in the study of Babylonian mathematics. But I think given that this usage seems to be fairly restricted to Sachs and some people quoting him, there is doubt as to how widespread it is. I have a suspicion that "regular number" may be used just as (in)frequently in other contexts. Additionally, nobody here is really knowledgable about that subject, so I'm leery of biasing this discussion on future rewrites. I think the best thing is just to delete and if someone writing about Babylonian mathematics needs an article on "regular number", then it can be created and written appropriately. --Chan-Ho (Talk) 16:14, 11 July 2006 (UTC)
• Keep Generalize to other bases. PrimeFan 21:38, 11 July 2006 (UTC)

Comment. No citation has been offered (not even Mathworld) for the generalization to other bases. Generalization seems like original research WP:NOR to me. I would appreciate it is somebody who is in favor of generalization could explain how such an article would meet the original research criteria and the verifiability WP:V criteria, which says The threshold for inclusion in Wikipedia is verifiability, not truth. CMummert 21:51, 11 July 2006 (UTC)

Comment Repeating point made above ... my own objection to including generalisation of "regular" to other bases is that it is both trivial and uninteresting. Every non-integer rational number is "regular" in an infinite number of bases - it is simple to determine which ones - and not "regular" in an infinite number of other bases. No irrational number is "regular" in any base. Only integers are "regular" in all bases. None of this is rocket science ! Gandalf61 07:49, 12 July 2006 (UTC)

Comment I'm no math-head, but is it possible (I ask genuine math-heads) that the PDF I mentioned before could be in any way be cited? TBH, I got the feeling on finding it that this 'regular number' stuff was obscure to the point of 'specialised/obsolete'. Maybe Mathworld only mention it out of some archaic tribute or other? And I am not really (again, as a non-math-head) convinced at the end of the day that this is a particularly standard term for a current and non-ancient notion of what it describes. Mathworld alone, in this case, is not enough IMO. And generalisation definitely needs proper sources. --DaveG12345 22:45, 11 July 2006 (UTC)

• Delete per nom, simple. Melchoir 02:53, 12 July 2006 (UTC)
• Keep. Term may be used in several ways, and not really a necessary term, but the appearance on mathworld is enough to convince me of significance. --TeaDrinker 04:13, 12 July 2006 (UTC)
  • Wikipedia is not a backup service for unreliable websites. Have you read through this AfD? Melchoir 06:23, 12 July 2006 (UTC)

• Yes, thank you for checking. Indeed, I concur the citations in Mathworld leave much to be desired (the principle editor Eric Weisstein, I am not conviced always reads the citations in mathworld; I take them to be suggested further reading rather than references). Additionally, I never heard the term "regular number" while I was getting my BS in math. Having said that, mathworld is not given to the creation of neologisms in my experience. I am not convinced the article is comprehensive in its descriptions of useages, but further checking on MathSciNet indicates thirty articles which use the term "regular number." There are several references to TA Springer's "Theory of regular numbers." I have not had time to look up and digest these references (and they may use a different definition). However there seems to me to be evidence the term is used. --TeaDrinker 22:55, 12 July 2006 (UTC)

• Delete not listed in the Oxford dictionary of mathematics, or the OED. Ubermichael 22:32, 12 July 2006 (UTC)

The above discussion is preserved as an archive of the debate. Please do not modify it. Subsequent comments should be made on the appropriate discussion page (such as the article's talk page or in a deletion review). No further edits should be made to this page.