Talk:Friendly number

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I agree with the unsigned comment below that the description here is difficult to understand and weak .

Weisstein has not attempted a description under this title , preferring the more logical alternative of placing it in the article titled FriendlyPair .

His description is better than the one here and so is the one in my article , http://upforthecount.com/math/mandrill.html

As copyright holder , I hereby grant Wikipedia a perpetual , non-exclusive , worldwide license to reproduce within Wikipedia under GFDL my descriptions of abundancy , friendlies of various sorts , and exclusive multiple from that article .

Use of the term kinship instead of abundancy is particularly inappropriate , and "club" seems questionable , although I can't immediately think of a better alternative .

I would tend to use "the 2-friendlies" or "the 7/3-friendlies" , "friends of abundancy = 4" or "those of abundancy = 5/2" .

I'm probably not the right one to rewrite this article , though I may eventually be able to do so .

Walter Nissen 2008-02-13 20:07 20:07, 13 February 2008 (UTC)


Please make this page more simple to understand! —Preceding unsigned comment added by 74.161.211.209 (talk) 15:50, 21 October 2007 (UTC)

Search bar takes you to amicable numbers[edit]

When I type "friendly numbers" in the wiki search bar (on the left of the main page) it takes me to Amicable numbers. I don't know how to fix this.Zain Ebrahim 07:42, 7 June 2007 (UTC)

When you get to a page via a redirect, there is a line below the title with a link to the redirecting title. You can click that link and edit the redirect. I have changed Friendly numbers and Friendly Pair so they redirect to Friendly number. I found the earlier redirect on Friendly Pair via "What links here" on Amicable number. PrimeHunter 11:41, 7 June 2007 (UTC)
It's still not working. When I clicked on Friendly Numbers above it took me to Amicable numbers. When I clicked on the redirect page from there everything seemed in order. I'm not sure why this isn't working.
Zain Ebrahim 13:17, 7 June 2007 (UTC)
Ok it's working now.Zain Ebrahim 07:21, 8 June 2007 (UTC)
You probably had a cached version of Friendly numbers from before I changed the target. When you click the redirecting link on the target page, the URL is different (in order to show the redirect page instead of following the redirect), so it wasn't cached. PrimeHunter 14:09, 8 June 2007 (UTC)

Lead Paragraph[edit]

Is very confusing and seems to beat around the bush.. It doesn't help that the first example (6, 28, 496) are also all perfect numbers, which no explanation given. —Preceding unsigned comment added by CallipygianSchoolGirl (talkcontribs) 05:16, 14 April 2008 (UTC)

Does the edit [1] help? PrimeHunter (talk) 14:47, 14 April 2008 (UTC)
It's a mild improvement, but the introduction still needs some work and a better example.--AaronRosenberg (talk) 17:19, 14 April 2008 (UTC)
What about [2]? (6, 28) is the smallest and simplest example, but not typical since the kinship is an integer. I pointed that out and made the smallest non-integer example later. PrimeHunter (talk) 22:35, 14 April 2008 (UTC)

Removal of "imaginary friends" pun[edit]

I see the "popular culture" section of this article has been removed without saying why. Although I have no vested interest in it one way or the other, I liked the pun. Of course, if removing the section improves this article, then I'm all for it. But the article doesn't seem any better now, without that section. Was the topic simply not notable?—GraemeMcRaetalk 16:01, 12 March 2009 (UTC)

Friendly pair notation[edit]

@Nnemo: Do you have a reliable source for writing a friendly pair as {a, b}? I haven't seen it before. It's the notation for a set (mathematics) but a friendly pair is usually written (a, b), including in the reliable source http://mathworld.wolfram.com/FriendlyPair.html in the article. You need a better source to change away from that and you haven't given a source at all. (a, b) is also common notation for pairs in general, not just friendly pairs. PrimeHunter (talk) 09:37, 14 May 2014 (UTC)

One of the first things one learns in maths in high school is not to confuse a couple and a pair.
(1 ; 4) is a couple, and it is different from (4 ; 1)
{1 ; 4} is a pair, and it is equal to {4 ; 1}
In a maths article, writing a couple while calling it a pair is a bad idea. The best solution is to say friendly couple. It would be consistent with what follows in the article : we have triplets (a ; b ; c) and lists (a ; b ; c ; d ; e).
--Nnemo (talk) 10:15, 14 May 2014 (UTC )
Those semicolons look odd to me. Mathematical notation is not universal and the preferred notation at your high school doesn't trump reliable sources. Wikipedia uses common names and doesn't invent new names for existing concepts so we definitely shouldn't use your made up name "friendly couple". The Google search "friendly couple" "friendly numbers" gives no relevant hits while "friendly pair" "friendly numbers" gives plenty, and they generally either write (a, b) or say "a and b" without specific notation. As a compromise I suggest we avoid the notation issue by saying "a and b". Whatever we do, it should be consistent within the article so if we change (6, 28) like you insist on then we should make the same change for (30, 140). PrimeHunter (talk) 20:53, 14 May 2014 (UTC)
OK for saying “a and b”. Or even “a, b”. --Nnemo (talk) 09:15, 15 May 2014 (UTC)
I have edited the article to say "a and b".[3] PrimeHunter (talk) 10:31, 15 May 2014 (UTC)