Wikipedia:Reference desk/Archives/Mathematics/2015 February 14

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February 14[edit]

Polygon with 1,000,000 sides[edit]

Wikipedia (but no other site I've visited) calls a 1,000,000-sided polygon a megagon. This term is clearly not consistent with how polygons are named. The prefixes penta-, hexa-, etc. have existed since the Greek language has diverged from other Indo-European languages, and literally refer to the number. Mega- (which literally means great) meaning 1,000,000 is a 19th-century coinage intended to be used as an SI prefix; I can't find any basis of the statement that it was also intended to be used as a general numerical prefix; its use as a general numerical prefix is like calling the number "great" instead of "one million" when using English names. Anything I need to know here?? Georgia guy (talk) 15:54, 14 February 2015 (UTC)[reply]

Wikipedia is based on sources. The opening sentence of megagon defines it and has two references. Google easily finds other mentions. It's not as established as pentagon or hexagon but it certainly isn't a Wikipedia invention. I don't know whether the Greeks had a word for it but the naming of geometric objects didn't suddenly stop after the Greeks. And many non-SI terms use Mega for million (or sometimes 220 = 1048576), for example megabyte, megapixel, megaprime (megadigitprime would perhaps have been more logical). We base our articles on what things are actually called and not whether it follows some old intention. Languages evolve. PrimeHunter (talk) 17:07, 14 February 2015 (UTC)[reply]
[ec]
  1. A Google search reveals several places where "Megagon" is mentioned.
  2. The Megagon article itself cites two sources which use the term, as an encyclopedic article should.
  3. "Mega" doesn't mean a million in Greek, true. But it does mean a million in modern usage, and it has Greek roots, so it seems like a natural continuation of polygon naming conventions.
  4. The reference desk isn't the best place to suggest corrections to articles. Wikiproject Mathematics is more applicable. You can also discuss it at the article talk page - which you did, 3 years ago.
-- Meni Rosenfeld (talk) 17:10, 14 February 2015 (UTC)[reply]
The term may be a neologism. Google Ngram Viewer seems not to have the word in its English corpus covering 1800 through 2000 [1]. I don't know if the word is established enough to deserve to be the title of a Wikipedia entry. The word being used by Wikipedia may affect adoption of its usage. It's possible that Wikipedia is not merely conforming to the word's usage, but in effect promoting it. --98.114.146.37 (talk) 19:14, 14 February 2015 (UTC)[reply]
Wiktionary has a couple of cites, but they are both from this century. No other dictionary has the word (yet). Dbfirs 19:31, 14 February 2015 (UTC)[reply]


I think I have heard/seen the term "megagon" with quite a different meaning — a polygon with "mega" sides, where "mega" is 2 in a pentagon (originally, 2 in a circle) in Steinhaus–Moser notation. The context was to be able to name the number "2 in a megagon". I'm not sure whether this meaning can be found in "reliable sources" or not. --Trovatore (talk) 23:15, 14 February 2015 (UTC)[reply]
This page implies the existence of a source for the definition of Moser's number (2 in a megagon) dating from June 1979 or earlier. Double sharp (talk) 15:02, 15 February 2015 (UTC)[reply]

If you want to be linguistically minded about it, the expected Greek form would be hecatontakismyriagon, given ancient Greek ἑκατοντάκις μύριοι (-ριαι, -ρια) for 106 (from Archimedes, literally 102 × 104). This is probably related to modern Greek εκατομμύριο (106). The 105-gon would be the decakismyriagon, the 107-gon the chiliakismyriagon, and the 108-gon the myriakismyriagon. However, I think all these names are on worse standing than megagon: at least the latter is actually used. An obvious solution that would satisfy the requirement for using a common name and a desire for being correct would be just to title the article 1000000-gon, Million-sided polygon, or something similar. (ED: Just after writing that, I made those two redirects to megagon.) Double sharp (talk) 14:48, 15 February 2015 (UTC)[reply]

I think that for these names we ought to check how many sources independently derive them the same way: certainly you would get lots of sources for 1–20, 30, 40, 50, 60, 70, 80, 90, 100, 1000, and 10000, but I'm not sure about 106, given that there are only two sources given and most of the philosophy refs in that book just refer to it as a polygon with a million sides, or some other descriptive phrase. (Whereas the philosophy refs do use "chiliagon" and "myriagon" for the 1000-gon and 10000-gon respectively.) Double sharp (talk) 15:02, 15 February 2015 (UTC)[reply]

zeros of zeta function[edit]

what is formula or function to calculate zeros of zeta function I want to know what's function — Preceding unsigned comment added by 151.236.166.36 (talk) 19:34, 14 February 2015 (UTC)[reply]

Your question was already answered. Sławomir Biały (talk) 21:46, 14 February 2015 (UTC)[reply]