Talk:Number of derangements

Re: named after Mehdi Hassani (vgl. Gaußklammer.)

Reference? Mehdi Hassani

At last: http://mathworld.wolfram.com/Subfactorial.html

and

A000166

and

http://www.cs.uwaterloo.ca/journals/JIS/VOL6/Hassani/hassani5.pdf

--Karsten Meyer 09:02, 19 December 2010 (UTC)

Hi Karsten, nice that you have a reference. Please give this reference on the page, best on the bottom of the page, in a section 'References'. And are you sure that Hassani invented this formula? If you are, then please be more specific and point to the page (or number of the formula) where you think it originated. If not, just give the reference (which is a good one). One should be very careful when attributing a formula to a person. Peter Luschny 19:44, 19 December 2010 (UTC)

I am not sure, that Hassani is the inventor. I took this from http://de.wikipedia.org/wiki/Subfakult%C3%A4t. I worked on this article, but the hassani part is from another person.

The formula is AFAIK ok, but if it is from hassani???

--Karsten Meyer 20:36, 19 December 2010 (UTC)

What is? vgl. Gaußklammer (I know that Gauß is Gauss in German, what about vgl. (see? or cf.?) and klammer?) — Daniel Forgues 06:58, 19 December 2010 (UTC)

Gaußklammer means this: $\lfloor x\rfloor$. The english word for "Klammer (mathematisch)" is bracket. But here is the meaning floor or ceiling (http://en.wikipedia.org/wiki/Floor_and_ceiling_functions). --Karsten Meyer 08:51, 19 December 2010 (UTC)

Yes, Gaußklammer is the floor function. So why did you not use this name? Well, I think I know the problem :) Here my trick in such a case: I go to German Wikipedia, look up 'Gaußklammer', then click at the left hand side on 'English', and voilà... Peter Luschny 19:44, 19 December 2010 (UTC)

I took all from http://de.wikipedia.org/wiki/Subfakult%C3%A4t (German Wikipedia). I used the trick (I go to German Wikipedia, look up 'Gaußklammer', then click at the left hand side on 'English'), as you can see above. --Karsten Meyer 20:36, 19 December 2010 (UTC)

By the way: The author arbol01 in de.wikipedia.org am i. --Karsten Meyer 20:36, 19 December 2010 (UTC)

OK, Karsten, so we will only cite Hassani's paper, as obviously some things are taken from it. However, the format can still be enhanced. Look at http://en.wikipedia.org/wiki/Derangement in the section 'External links'. This looks much nicer.

 | author = Hassani, Mehdi
 | title = Derangements and Applications
 | publisher = Journal of Integer Sequences (JIS), Volume 6, Issue 1, Article 03.1.2, 2003
 | url = http://www.cs.uwaterloo.ca/journals/JIS/VOL6/Hassani/hassani5.html}}

 | author = Weisstein, Eric W
 | authorlink = Eric W. Weisstein
 | title = Derangement
 | publisher = MathWorld–A Wolfram Web Resource
 | url = }}

Ah, Wikipedia uses a template which is not on this wiki. So we have to do it by hand.

• Mehdi Hassani, Derangements and Applications, Journal of Integer Sequences, 6(1), Article 03.1.2, 2003.
• Eric W. Weisstein, Derangement, MathWorld–A Wolfram Web Resource, as of 2010-12-19.

Peter Luschny 23:05, 19 December 2010 (UTC)

Re: templates for references

I tried some time ago to get the the following Wikipedia templates

Template:Citation/core, Template:Citation/core/doc,

Template:Citation, Template:Citation/doc,

Template:Cite arXiv, Template:Cite arXiv/doc,

Template:Cite book, Template:Cite book/doc,

Template:Cite journal, Template:Cite journal/doc,

to work within the OEIS, but they are dependent on so many other Wikipedia templates that it is not easy to disentangle from Wikipedia...

I will work some more on them (any help on those would be great too,) and if I don't succeed on disentangling those templates then I will have to start from scratch. Also, we would need to get approval from Neil Sloane and David Applegate before starting using them, in case they have other plans (there are many different referencing conventions.) — Daniel Forgues 02:17, 20 December 2010 (UTC)

For more on this, check Style Sheet#Style sheet for contributors to OEIS Wiki (latest info may still be in draft...) — Daniel Forgues 03:35, 20 December 2010 (UTC)

Check also Talk:Style Sheet#Re: templates for references. — Daniel Forgues 07:44, 20 December 2010 (UTC)

Using Cite journal (for traditional print)

{{Cite journal
| author = Hassani, Mehdi
| title = Derangements and Applications
| publisher = Journal of Integer Sequences (JIS), Volume 6, Issue 1, Article 03.1.2, 2003
| url = http://www.cs.uwaterloo.ca/journals/JIS/VOL6/Hassani/hassani5.html
}}

thus obtaining

Hassani, Mehdi. Derangements and Applications. Journal of Integer Sequences (JIS), Volume 6, Issue 1, Article 03.1.2, 2003. http://www.cs.uwaterloo.ca/journals/JIS/VOL6/Hassani/hassani5.html. 

almost works (except for that spurious web link at the end...)

Using

{{Cite web
| author = Hassani, Mehdi
| title = Derangements and Applications
| publisher = Journal of Integer Sequences (JIS), Volume 6, Issue 1, Article 03.1.2, 2003
| url = http://www.cs.uwaterloo.ca/journals/JIS/VOL6/Hassani/hassani5.html
}}

thus obtaining

Hassani, Mehdi. “Derangements and Applications”. Journal of Integer Sequences (JIS), Volume 6, Issue 1, Article 03.1.2, 2003. http://www.cs.uwaterloo.ca/journals/JIS/VOL6/Hassani/hassani5.html. 

almost works (except for that spurious web link at the end...)

I'll look for why that happens, anybody got a clue? It doesn't in Wikipedia. — Daniel Forgues 10:59, 20 December 2010 (UTC)

Re: MathWorld template

For links to MathWorld, we have a template (see Style Sheet#Style sheet for contributors to OEIS Wiki, latest info may still be in draft...) — Daniel Forgues 03:03, 20 December 2010 (UTC)

Currently, the MathWorld template does not italicize the link (Wikipedia does not italicizes web page titles but quotes them), we may modify the style of the link later... — Daniel Forgues 06:53, 20 December 2010 (UTC)

The behaviour of the MathWorld may be changed: cf. Talk:Style Sheet#Re: MathWorld template and Template talk:MathWorld — Daniel Forgues 07:44, 20 December 2010 (UTC)