User talk:MFH

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fr-5 Cet utilisateur parle français à un niveau professionnel.
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als-1 Dä Bnutzer verfüegt über Basis-Kenntnis vom Alemannische.
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Welcome to my talk page! Click here to drop me a message, or edit any existing section to add a comment.

Note that I try to organize this a bit. If you came here for something you can't find anymore, it's most probably in one of the subcategories like /math, /phil or /wiki.

All such subpages are linked to below under a corresponding "toplevel category" section title (e.g. "Mathematics").

Sorry for any inconvenience. (Feel free, anyway, to drop me a message about any subject on the bottom of this page.)

Original Welcome message[edit]


Hello, MFH, and welcome to Wikipedia! Thank you for your contributions. I hope you like the place and decide to stay. Here are a few good links for newcomers:

I hope you enjoy editing here and being a Wikipedian! Please sign your name on talk pages using four tildes (~~~~); this will automatically produce your name and the date. If you need help, check out Wikipedia:Where to ask a question, ask me on my talk page, or place {{helpme}} on your talk page and someone will show up shortly to answer your questions. Again, welcome! 

Thanks for your contribution to sequence. Just one note, you don't need to write the underscore in net (topology); as the wikipedia software will do it for you.

Enjoy! Oleg Alexandrov 23:03, 8 Mar 2005 (UTC)

I knew I didn't need to, but I thought it would "save server resources".
Admittedly, it looks ugly, and if usage is such, I won't put it ever again.

MFH 01:59, 10 Mar 2005 (UTC)

(continued on /phil#Welcome)


Comments concerning mathematics now are found at User talk:MFH/math.

Philosophical discussions and such[edit]

Philosophical, epistemological and similar discussions (from discussions about usage of punctuation marks to the meaning of life and the universe) now are found at User talk:MFH/phil.

Wikipedia related[edit]

User talk about wiki technicalities: "do"s and "don't"s, from netiquette to browser problems, is now mainly found at User talk:MFH/wiki (but might also be in User talk:MFH/phil).


The remainder of this page concerns either things not not belonging to one of the preceding categories, or juste those recent messages I had not yet time to move to the archive.


I haven't updated that link -- try Longest word in English#Jokes. MikeStorm 01:19, 13 May 2005 (UTC)

WP' style formal definition[edit]

Now if I really think of it, do we indeed always need to put formal definitions? Somehow, I always thought that what Wikipedia should be about is having a fine collection of essays about mathematics written at an accessible level. And an essay should not always be rigurious or formal. But this is my own very private opinion. I wonder how people indeed think of this issue. Oleg Alexandrov 23:24, 24 May 2005 (UTC)

You must know of pages (eg Talk:Polynomial) from where it is clear that much more than 1% (I estimate at least 30%) of all writers of math articles do not agree.
And I referred to a WP guideline (How mathematics.)
And the definition of "definition" (not equal to "explanation") and "encyclopedia" (not equal to "collection of essays") do not depend on our opinions. MFH: Talk 00:19, 25 May 2005 (UTC)
Got it. I just don't like when articles get burdened with too much rigor as that usually makes them less penetrable to nonmathematicians. By the way, I replied on my talk page to your "subject" question. Oleg Alexandrov 21:55, 25 May 2005 (UTC)

Red links[edit]

User:Charles Matthews/red links is just a collection of fairly interesting links, from a few places (the Dieudonné analysis books, Griffiths & Harris are two I went through). It is a 'project page' like any other, in the sense that anyone can use the suggestions. Redirecting is OK, in general. Charles Matthews 14:26, 25 May 2005 (UTC)

empty product[edit]

The following program woud be indeniably better:

sum := x(1)
prod := x(1)
for i := 2 to 10 do
sum := sum + x(i)
prod := prod * x(i)

I maintain that this philosophical "problem" has its root in the question of counting: Do you start with the first member to count, or before counting the first member. — MFH: Talk 23:32, 21 Jun 2005 (UTC)

PS: indeed, depending on what are the objects to sum and multiply, O and 1 are not the same. E.g. a computer algebra program could give you an error if the x(i) were matrices and it would not allow the scalar 0 (resp 1) to be added to (resp multiplied by) a matrix. But I agree on the following:

The empty sum (resp. product) of objects in X should be the neutral element for addition (resp multiplication) in X.

Remains to know what is the neutral element for the (cartesian) product of sets. MFH: Talk

Who ever said there's either a problem or a matter of philosophy? Your quotation marks around "problem" make it look as if someone other than you saw a problem here, or otherwise used that word. Michael Hardy 23:51, 21 Jun 2005 (UTC)
PS: "Indeniably"? Did you mean "undeniably"? Certainly your algorithm is NOT better, since it incorrectly starts the sum at 1 rather than 0. Michael Hardy 23:51, 21 Jun 2005 (UTC)

No, you are wrong (not on "undeniably", though): The task is to add and multiply items x(i) starting with x(1). And, as I said, the other program is not correct since 0 and 1 are not necessarily of the same type than the x(i).

Indeed, I put "problem" since it is not a true problem, just a matter of convention. Not even a convention about the contents (where all agree upon), but just on how to speak about... just a naming convention, in some sense. MFH: Talk 00:00, 22 Jun 2005 (UTC)


When googling quasilinear, there are many links to "Quasilinear Parabolic/Elliptic Differential Equations". Since I don't know what they are, or if they are related to your O(...) functions, let's make a disambiguation page. --J heisenberg 12:47, 23 Jun 2005 (UTC)

No this is not related at all. For the DE quasilinear means that the coefficients are not constants but (given) functions. For the growth/complexity, quasilinear means O( n^a ) for all a>1 (or more restrictedly O( n log n)). MFH: Talk 13:03, 23 Jun 2005 (UTC)

WikiFun Round 9: Lightning Round Time[edit]

I have decided to attempt to advance and end the round quickly. Parts of the question will be revealed with more hints and/or be more elaborated on as every two days. I have currently provided more hints on the answer pages for the current remaining questions. --AllyUnion (talk) 08:32, 6 August 2005 (UTC)

Please vote[edit]

Hello. Please vote at Wikipedia:Featured list candidates/List of lists of mathematical topics. Michael Hardy 22:58, 14 October 2005 (UTC)

Definition of a series[edit]

Hi MFH, I've just replied to an issue you raised on Talk:Series (mathematics) back in April. Whaddaya think? Melchoir 02:21, 5 December 2005 (UTC)


Hi, I've noticed you've taken part in Wikifun before.

Just to let you know, Round 11 begins today at 0900 GMT. Dmn 04:26, 8 December 2005 (UTC)

Wikifun round 12[edit]

This is to invite you to participate in the next game of Wikifun.
Round 12 will begin at 11:00 UTC on Friday January 20. 2006.
-- Ravn 17:19, 18 January 2006 (UTC)


It's easy - click on history, then on the version you want to revert to. Edit that page and ignore the warning message, then submit the page without modifying it. The Help:Contents section is a good place to find information like this. Let me know if you have any more questions. Feezo 22:22, 17 February 2006 (UTC)

Biscuit Tortoni[edit]

Biscuit Tortoni is not a brand name, it is a type of ice cream dish like baked alaska. I will change the stub categorization to {{dessert-stub}}. Thanks for being bold! -- Avi 03:21, 23 February 2006 (UTC)


You've just won round 12 of Wikifun! :) Would you like to devise the villa^Wquestions for the next round? Oh, and what's your favourite flavour of Kellogg's and where should it be shipped to? -- Ravn 20:17, 7 March 2006 (UTC)

(answered on User talk:Ravn) — MFH:Talk 23:05, 7 March 2006 (UTC)

Re:mind bending[edit]

I guess the page isn't clear enough... You have to answer the questions, and if you want, review some articles. I see the questions are a bit hidden. I hope you participate! Here are the instructions:

Question set 1 (created by myself)
Question set 2 (created by Celestianpower)

There are also some fake articles that may serve for background on answering the questions.

Article for Set 1
Article for Set 2

You can also review these articles, it's very simple. Just read them and place a new section on the talk page ("Evaluation by MFH") giving a score from 1 to 10 for each section:

   * Comprehensiveness
   * Creativity
   * Likeness in formatting to actual article
   * Graphics
   * Wording/Style
   * Humor
   * Overall
   * Other comments (this should not have a score :) )

Having that said, what can I do to explain that better on the WP:MIND page? I was thinking in joining the two sets and tallies on one, it would be much better. Any suggestions on the format, scoring, etc. would be appreciated (and needed).

P.S: By the way, if you can't answer any of the questions I have some hints ready to be put soon. Fetofs Hello! 23:55, 7 March 2006 (UTC)

Wikifun talk[edit]

It coincided with Wikipedia crashing, so I assumed the page was blanked as a result of the bug. In fact Wikifun talk page was the first page I saw during the time that Wikipedia was malfunctioning, and it looked like it never existed. So you can understand why I thought that the blanking was not deliberate.  Grue  22:03, 14 March 2006 (UTC)


What question? If you believe you have the right answer you can tell me and I'll give you the points anyway... Fetofs Hello! 23:17, 31 March 2006 (UTC)

You can do the questions, however you won't get the article bonus points for writing an article; I could still get you 1 to 3 points for helping out. Fetofs Hello! 22:36, 6 April 2006 (UTC)


Thank you for letting me know. Unfortunately I am not a sys-op and can't block. I'll keep an eye on it but luckily it looks like that IP address has been dormant for a few days now. -- Renesis13 05:45, 4 April 2006 (UTC)

Trees instead of taxoboxes[edit]

I like the idea of trees instead of taxoboxes, is there some way they can created by code in Wikipedia, though? The can also be easily used to show questionable relationships, or plop two competing trees down. They're much easier to grasp, imo, than taxoboxes, yet the latter remain useful in the absence of trees, when done correctly. KP Botany 20:15, 3 November 2006 (UTC)

Haag-Lopuszanski-Sohnius theorem[edit]

Name: Martin Sohnius
Email: msohnius@ followed by
Subject: Haag-Lopuszanski-Sohnius Theorem
Thanks for putting my name into Wikipedia!  It feels good, after all these years.


I just received the above message, which I believe was meant for you. I started the talk page of the article, while you started the article itself; I think he got the histories of the two confused. Mike Peel 17:22, 5 December 2006 (UTC)


Round 14 is starting just about now. --Spondoolicks 16:58, 10 April 2007 (UTC)

Well what can I say? You've got to stay on your toes in the fast-moving world of Wikifun :) Hopefully we won't be waiting the best part of a year for the next round this time. --Spondoolicks 14:29, 23 April 2007 (UTC)

No content in Category:Images of kitchenware[edit]

Information icon.svg

Hello, this is a message from an automated bot. A tag has been placed on Category:Images of kitchenware, by another Wikipedia user, requesting that it be speedily deleted from Wikipedia. The tag claims that it should be speedily deleted because Category:Images of kitchenware has been empty for at least four days, and its only content has been links to parent categories. (CSD C1).

To contest the tagging and request that administrators wait before possibly deleting Category:Images of kitchenware, please affix the template {{hangon}} to the page, and put a note on its talk page. If the article has already been deleted, see the advice and instructions at WP:WMD. Feel free to contact the bot operator if you have any questions about this or any problems with this bot, bearing in mind that this bot is only informing you of the nomination for speedy deletion; it does not perform any nominations or deletions itself. --Android Mouse Bot 2 11:43, 20 May 2007 (UTC)

I have no objection - IIRC, some time ago I tried to organize several "images of ..." categories, and in particular there was a request for organizing pictures into an appropriate category of that type, but these seem to have disappeared... — MFH:Talk 20:56, 28 February 2008 (UTC)

Twin, sexy and related primes[edit]

I have added a section about conjectured prime gap densities to Polignac's conjecture‎. I'm not sure it's good for an article about a specific prime gap to discuss the conjectured density of other prime gaps. But I plan to add the conjectured densities of the forms themselves to cousin prime and sexy prime.

The meaning of terms in Wikipedia should be based on reliable sources and not on what seems more reasonable based on the personal views of the editors. The MathWorld reference in sexy prime says "There is only a single sexy quintuplet, (5, 11, 17, 23, 29)". I haven't seen another definition, but I can understand why you would like it. The MathWorld definition gives a single trivial quintuplet and is not equivalent to the normal definition of a prime k-tuplet which is k primes as closely together as admissible when considering potential prime factors. But I'm not sure how that should be "translated" to sexy primes when being a sexy prime is dependent on another number being prime. Maybe a sexy quintuplet should be 5 primes of 6 numbers in an arithmetic progression (p, p+6, p+12, p+18, p+24, p+30). But if p+6 or p+24 is composite then such a "sexy quintuplet" can contain a prime which is not a sexy prime. For example (41, 47, 53, 59, 71) where 65 is composite and 71 is not a sexy prime. An alternative definition would be something like: A sexy prime k-tuplet is k primes of form p+6n which are all part of a sexy prime pair with at least one of the others, and are as closely together as admissible for k such primes. But that's complicated and not fully equivalent to prime k-tuplets. Sexy prime quadruplets are rarely studied (I'm one of few people who have searched them and found the largest known), so I guess nobody has seriously considered an extended definition (before us now!). Wikipedia shouldn't make one up. PrimeHunter (talk) 02:03, 8 April 2008 (UTC)

If you removed the "sexy prime quintuplet" name from sexy prime but kept the note that (5,11,17,23,29) is the only occurrence of that pattern then I wouldn't object. I sometimes contact Eric about errors and suggested additions of published material, but generally not about other content issues like unsourced definitions, and I'm not sure what I would suggest as alternative definition. There is no clear choice and I haven't heard of anybody studying "sexy" patterns with more than 4 primes. But if you want to suggest something to Eric then go ahead. PrimeHunter (talk) 21:10, 8 April 2008 (UTC)
I did a little original research (unsuited for Wikipedia). The closest admissible patterns of 14 primes with same value modulo 6 have difference 102 between start and end. An example of one of the patterns with 20-digit primes:
97234709270276941661 + 6n for n = 0, 1, 2, 3, 5, 6, 7, 8, 10, 12, 13, 15, 16, 17.
It contains two sexy quadruplets, a non-sexy prime, a sexy pair, and a sexy triplet. These subpatterns are each separated by one composite. PrimeHunter (talk) 12:49, 9 April 2008 (UTC)
More original research. The first case of 4 sexy prime quadruplets as closely together as admissible (might be called a "sexy prime quadruplet quadruplet") is:
2327074306453592351 + n for n = 0,6,12,18, 50,56,62,68, 90,96,102,108, 120,126,132,138 (n = 110 gives a non-sexy prime). The second quadruplet has another value modulo 6. PrimeHunter (talk) 00:56, 15 April 2008 (UTC)
I used my own unpublished C program which uses the GNU Multi-Precision Library for probable prime testing. It has set a lot of records for different prime patterns since 2003. I got cpu time for the above result after finding the largest known 15-tuplet a couple of days ago after a long search. PrimeHunter (talk) 15:06, 16 April 2008 (UTC)
Prime Curios! is now listing it at I emailed you 17 April but don't know whether it got through. The mail had a link to a page which has since moved to PrimeHunter (talk) 22:23, 27 April 2008 (UTC)

Aitken method[edit]


It appears that you've added a section on the Aitken method to Series acceleration, however, that section has an error in the formula, as noted on the talk page. Could you fix this? Thanks. linas (talk) 03:39, 2 June 2008 (UTC)

I see that Loisel made a bit of a mess with his merging and moving about; thanks for fixing that up. linas (talk) 17:06, 2 June 2008 (UTC)
I resurrected the old series acceleration, (appearently I'd written it long ago, and forgotten about it). It had been made a redirect when its contents was merged into sequence transformations. I moved much of the content (back to) there. I think that improves things, although clearly much more could be done. linas (talk) 18:35, 2 June 2008 (UTC)

RfD nomination of Vanity page[edit]

I have nominated Vanity page (edit | talk | history | protect | delete | links | watch | logs | views) for discussion. Your opinions on the matter are welcome; please participate in the discussion by adding your comments at the discussion page. Thank you. MBisanz talk 15:34, 7 November 2008 (UTC)

Unreferenced BLPs[edit]

Information.svg Hello MFH! Thank you for your contributions. I am a bot alerting you that 2 of the articles that you created are tagged as Unreferenced Biographies of Living Persons. The biographies of living persons policy requires that all personal or potentially controversial information be sourced. In addition, to insure verifiability, all biographies should be based on reliable sources. if you were to bring these articles up to standards, it would greatly help us with the current 3,435 article backlog. Once the articles are adequately referenced, please remove the {{unreferencedBLP}} tag. Here is the list:

  1. Eugène Cremmer - Find sources: "Eugène Cremmer" – news · newspapers · books · scholar · HighBeam · JSTOR · free images · Wikipedia library
  2. Bernard Julia - Find sources: "Bernard Julia" – news · newspapers · books · scholar · HighBeam · JSTOR · free images · Wikipedia library

Thanks!--DASHBot (talk) 19:19, 8 January 2010 (UTC)

Articles for deletion nomination of Branch (graph theory)[edit]

Ambox warning pn.svg

I have nominated Branch (graph theory), an article that you created, for deletion. I do not think that this article satisfies Wikipedia's criteria for inclusion, and have explained why at Wikipedia:Articles for deletion/Branch (graph theory). Your opinions on the matter are welcome at that same discussion page; also, you are welcome to edit the article to address these concerns. Thank you for your time.

Please contact me if you're unsure why you received this message. RDBury (talk) 19:01, 28 January 2010 (UTC)

"Tensor notation" on "Talk:Hooke's law[edit]

I annotated one of your contribs (and another editor's that follows it) with

The following contrib was positioned at the left margin. Perhaps a colleague will offer an opinion of what earlier contrib it should be construed as commenting on.

Perhaps you'll consider either

indenting your contrib one level further than what you responded to, or
moving it into a new section.

(Or, if you believe your contrib is importantly related to the rest of the "Tensor notation" section's discussion, without being a response to anything in it, perhaps you'll consider starting a new subsection -- which i'll call "C" -- with that content, adding a section or sub-section heading, and perhaps adjusting the level of the "Tensor notation" heading, so that we end up with

== A ==
=== B ===
Other current content of "Tensor notation"
=== C ===
Your contrib current under "Tensor notation"

where either A or B is "Tensor notation", and you would come up with the titles for C and for whichever of A and B you don't designate as "Tensor notation". (Tho of course your priorities may appropriately lie elsewhere!)
--Jerzyt 19:15, 10 March 2010 (UTC)

Articles for deletion nomination of Eugène Cremmer[edit]

Ambox warning pn.svg

I have nominated Eugène Cremmer, an article that you created, for deletion. I do not think that this article satisfies Wikipedia's criteria for inclusion, and have explained why at Wikipedia:Articles for deletion/Eugène Cremmer. Your opinions on the matter are welcome at that same discussion page; also, you are welcome to edit the article to address these concerns. Thank you for your time.

Please contact me if you're unsure why you received this message. RedBlue82 talk 22:01, 2 September 2010 (UTC)

Sorry for not noticing the tag that had been added over 1 year... I added a liste of references according to google, and explicitely the one referred to in the text. This remains a stub, but "does not cite its sources" is no more true, and fortunately the vote was clearly to "keep". — MFH:Talk 13:55, 8 September 2010 (UTC)

Hi, Suslin cardinal includes Suslin line as a 'see also'. I have never come across any connection between them, but in case you know some way in which they are related, could you elaborate? I was planning to remove that link otherwise. Googling yielded no connection. Thanks. Chimpionspeak (talk) 16:15, 23 March 2011 (UTC)

answered on your talk page — MFH:Talk 04:23, 24 March 2011 (UTC)

Minus sign[edit]

Right, this sign is not U+002D. But U+2212 MINUS SIGN neither is a U+2013 en dash. It is true, although Google finds a lot of morons' gibberish that HTML does not possess "−", recommendations to use dashes etc. You can learn to distinguish such characters even without exploring their UCS code points, for example by copying and pasting a character to a string of several identical characters where they have different appearances.

Infix String Character
q-p ----- U+002D Hyphen-minus
q–p U+2013 en dash
q—p U+2014 em dash
q−p U+2212 minus sign

Unlikely that you will be surprised today by aforementioned discoveries, but this[1] your edit initiated a confusion which lasted for more than 6 years. Not all editors have an experience to distinguish minuses from dashes. Could you remember, in which else article did you put such easter eggs? Or, maybe, you just imitated some early editor?

Note: I am aware of existence of User talk:MFH/wiki and so, but nevertheless put my message here for a better visibility.
Incnis Mrsi (talk) 11:30, 12 January 2012 (UTC)

Maxwell's equations#Conceptual insight from this formulation[edit]

Greetings, MFH!

Your edit has existed peacefully for 6 years in Maxwell's equations. The article is evolving. When I was reading it this morning, I was quite alarmed to see that I no longer understood your contribution, based on the flow of the article as it now stands. Specifically, I can no longer understand the 'interaction term A J' expression.

Since the changes to the Maxwell's equations article are moving the searchlight to your contribution, I hope that you will amplify your long standing edit. Regards, --Ancheta Wis   (talk | contribs) 10:31, 31 March 2012 (UTC)

Disambiguation link notification for November 12[edit]

Hi. Thank you for your recent edits. Wikipedia appreciates your help. We noticed though that when you edited Space–time tradeoff, you added a link pointing to the disambiguation page Brute force (check to confirm | fix with Dab solver). Such links are almost always unintended, since a disambiguation page is merely a list of "Did you mean..." article titles. Read the FAQ • Join us at the DPL WikiProject.

It's OK to remove this message. Also, to stop receiving these messages, follow these opt-out instructions. Thanks, DPL bot (talk) 11:51, 12 November 2012 (UTC)

Dear Bot, in this case the DAB page was exactly what I wanted to link to. Please consider the possibility that I have checked and evaluated the different possible choices and made what seemed to me the best choice available. If you don't know better, you should not assume that s/o did not want to do what he did, in particular not w/o taking into account the user profile, number of contributions and seniority. — MFH:Talk 13:04, 12 November 2012 (UTC)

Article Feedback deployment[edit]

Hey MFH; I'm dropping you this note because you've used the article feedback tool in the last month or so. On Thursday and Friday the tool will be down for a major deployment; it should be up by Saturday, failing anything going wrong, and by Monday if something does :). Thanks, Okeyes (WMF) (talk) 21:25, 13 March 2013 (UTC)

Image without license[edit]

Unspecified source/license for File:Plot of number of primes between consecutive squares.png[edit]


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ArbCom elections are now open![edit]

You appear to be eligible to vote in the current Arbitration Committee election. The Arbitration Committee is the panel of editors responsible for conducting the Wikipedia arbitration process. It has the authority to enact binding solutions for disputes between editors, primarily related to serious behavioural issues that the community has been unable to resolve. This includes the ability to impose site bans, topic bans, editing restrictions, and other measures needed to maintain our editing environment. The arbitration policy describes the Committee's roles and responsibilities in greater detail. If you wish to participate, you are welcome to review the candidates' statements and submit your choices on the voting page. For the Election committee, MediaWiki message delivery (talk) 12:56, 23 November 2015 (UTC)

Weird number[edit]

Hey there, I hope you are doing well.I am just curious about the weird number talk and the following is written there:

"What's the point in the quoted result from the 1976 paper concerning very large weird numbers, given that if N is weird, Np is weird for all p>sigma(N) ? So taking p=M#44 (the largest known prime), we get a much larger weird number using any other weird number (provided its divisors' sum does not exceed M#44). — MFH:Talk 17:47, 4 April 2008 (UTC)

I haven't seen the paper, but I would guess the point was to construct a large primitive weird, ie one which has no weird factor (and therefore no abundant factor). Hv (talk) 08:00, 30 June 2012 (UTC)"

So what i wanted to know is that can you show me the proof of the statement Np is weird i am trying to look really hard into it but i cannot seem to find it even in the paper.I really appreciate your help thanks. Sarim. — Preceding unsigned comment added by (talk) 15:50, 7 December 2015 (UTC)

I should answer on your talk page but you connected anonymously. If p > sigma(N) then the divisors of Np, DIV(Np) are the divisors of N union these divisors times p : D(Np) = D(N) U p*D(N). Since N is not a sum of some of its divisors, Np cannot be either (because even adding all of N's divisors up is less than p, the smallest "step" possible in between multiples of p): Let X(N) be the set of numbers which are sum of a subset of D(N), then X(Np) = X(N) + p*X(N) (I think... maybe there's a typo here...?). Since N is not in X(N), Np is not in X(Np). - — MFH:Talk 20:55, 8 December 2015 (UTC)