Wikipedia:Articles for deletion/142857 (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 was keep. John254 02:32, 10 August 2007 (UTC)

142857 (number)

 * – (View AfD) (View log)

There is nothing special about this natural nubmer. There is an infinite number of numbers with such properties. Liransh 11:19, 5 August 2007 (UTC) ":Weak Delete Cyclic number is encyclopedic but every cyclic number is not. It might be better to handle this number on the cyclic number page and redirect from 142857 (number) to that article. Shabda 14:23, 5 August 2007 (UTC)
 * Weak keep If someone can find a source for "142,857 is the best-known cyclic number." then I think it should be kept. --PEAR (talk) 11:29, 5 August 2007 (UTC)
 * Comment. The following pages on cyclic numbers all use 142,857 as their example, which I think demonstrates that it's the most "notable" of this kind of number: The Internet Encyclopedia of Science, "The Alluring Lore of Cyclic Numbers" (The Two-Year College Mathematics Journal), PlanetMath.org, "Go figure", (Planet Doctor), etc etc. It's certainly the only one I'd heard of myself prior to reading this AfD. At worst I'd redirect to cyclic number, but given the content in both pages, I think cyclic number would be a bit overwhelmed and would become less readable for a passing reader, so I'd prefer to keep them. Meanwhile, I'll add these refs to 142857. --DeLarge 11:51, 5 August 2007 (UTC)
 * Further comment: it has its own 142857.com domain, and there are ten interwiki links. Also please note that while it's most notable as a cyclic number, it is also a Harshad number and a Kaprekar number (these are both already mentioned in the article). --DeLarge 15:15, 5 August 2007 (UTC)
 * Strong Keep thank you for the comment, I'm now changing my vote to strong keep. --PEAR (talk) 11:55, 5 August 2007 (UTC)
 * Merge the few bits that are significant and not already in Cyclic number to that article, and redirect. Deor 14:59, 5 August 2007 (UTC)
 * keep - there's no harm done on having an article on "the most well-known cyclic number". I certainly already knew it before I read this article (and the only other one I can think of is 1/11). Let's have more math articles and less articles on cartoons, eh? AllGloryToTheHypnotoad 15:11, 5 August 2007 (UTC)
 * Strong keep The article demonstrates the concept of a cyclic number better than any dictionary. In addition, 142857 is often referred to in those "fun with math" books that introduce kids to higher mathematics (see my new article, 142857 in popular culture... just kidding).  Granted, there will be people who say, "Numbers are NOT supposed to be fun!" but 142857 is more than a parlor trick.  Mandsford 15:44, 5 August 2007 (UTC)
 * Keep While I agree with Shabda that not every cyclic number is encyclopedic, this one is, being the best known in the number base we humans use, base 10. Anton Mravcek 19:04, 5 August 2007 (UTC)
 * Strong keep This cyclic number's use within the enneagram is sufficient reason for a separate article. Gabriel Kielland 20:27, 5 August 2007 (UTC)
 * Keep; much the simplest cyclic number, and the only case not complicated by having a zero in its expansion. Septentrionalis PMAnderson 21:35, 5 August 2007 (UTC)
 * Keep - smallest cyclic number, therefore notable. Gandalf61 10:35, 6 August 2007 (UTC)
 * Merge to Cyclic number after deleting some sludge like saying that this number is related to 22/7 which is "approximately pi." Really reaching for "amazing" properties.Not very impressed by the "Harshad" and "Kaprekar" properties because they are from the same source, Kaprekar, as in "D. R. Kaprekar, On Kaprekar numbers, J. Rec. Math., 13 (1980-1981), 81-82." People seem to love to glorify themselves by naming classes of numbers after themselves.  Edison 16:03, 6 August 2007 (UTC)
 * Keep. Many articles give examples of this number. It is shown as the first 6 decimal places of 1/7 as well as being the smallest cyclic number. -- Casmith_789 (talk) 16:16, 6 August 2007 (UTC)
 * Comment. According to WP:1729, it is interesting that 142857 is a cyclic number, but it's not that interesting that it's a Harshad number or a Kaprekar number. WP:NUM says at least three interesting properties are necessary to justify giving a number its own article. Knotslip12 21:23, 6 August 2007 (UTC)
 * Admittedly I didn't spend hours calculating, but using WP:1729 I thought that it was an "interesting" Kaprekar number. --DeLarge 17:01, 8 August 2007 (UTC)
 * Well, I ran thru most of the calculation and came up with the same result as you. However, I did not look at any papers, and I didn't test if 142857 is a Kaprekar number in other bases. Anton Mravcek 21:01, 8 August 2007 (UTC)
 * keep so maybe teh only intersting thing about 142857 is that its a cyclic number. But its just so damn famous as a cyclic number that maybe for this number we shuold make one very rare exception for WP:NUM's notability rules. try thes Gooogle search: "142857 -site:wikipedia.org" Numerao 18:41, 7 August 2007 (UTC)
 * Merge to cyclic number. It's only really notable for this one property, so no separate article is warranted. —David Eppstein 16:26, 8 August 2007 (UTC)
 * Keep or merge Everybody learns this number in childhood, because of its cyclic nature. Except those who don't.  The latter can learn it here. Michael Hardy 22:45, 8 August 2007 (UTC)
 * Keep. The nominator is wrong, this number is notable as clearly demonstrated above.  Please withdraw. Burntsauce 17:38, 9 August 2007 (UTC)

WP:1729 questionaire on this number

 * 1) How many n < 107 do NOT have this property in common with Number N? If it's too computationally intensive to calculate, a heuristic estimate is acceptable, or even a rough guesstimate. These are the starting points.
 * I guesstimate there are 50 Kaprekar numbers less than 10 million, hence we start with 9 999 950 points.


 * 1) Has a professional mathematician written a peer-reviewed paper or book about this property that specifically mentions Number N?
 * I can’t access Kaprekar’s paper right now, so I’m assuming it doesn’t specifically mention 142857. Now –50 points.


 * 1) In a list sorted in ascending order, at what position k does Number N occur? Deduct k from Question 2 points.
 * According to, 142857 is the 25th Kaprekar number. –75 points.


 * 1) . Might f(N) = False in a different base b?
 * It’s true in base 10, so that’s 10 points right there. But for each base in which it’s false, it’s a deduction of the base number times the number under consideration. But I don't have access to a CAS right now, so I’ll be charitable for now and award 10 points, so now at –65 points.


 * 1) Does the sequence of numbers with f(N) = True in Sloane's OEIS specifically list Number N in its Sequence or Signed field?
 * Yes it does, so that’s +6886 points, bringing this up to 149808 points.


 * 1) What keywords does the sequence have in its Keywords field?
 * A point for nonn, another 6886 for nice, a point for easy. 156696 points.

points > 0. The property in relation to the number is interesting. points = 0. It's your call. points < 0. The property in relation to the number is NOT interesting.
 * 1) How many points are there? 156696


 * 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.