User talk:Gandalf61

Nomination of Polydivisible number for deletion
A discussion is taking place as to whether the article Polydivisible number is suitable for inclusion in Wikipedia according to Wikipedia's policies and guidelines or whether it should be deleted.

The article will be discussed at Articles for deletion/Polydivisible number until a consensus is reached, and anyone, including you, is welcome to contribute to the discussion. The nomination will explain the policies and guidelines which are of concern. The discussion focuses on high-quality evidence and our policies and guidelines.

Users may edit the article during the discussion, including to improve the article to address concerns raised in the discussion. However, do not remove the article-for-deletion notice from the top of the article. Prova-nome (talk) 03:01, 9 October 2019 (UTC)

Penrose tiling
Penrose tiling, an article that you or your project may be interested in, has been nominated for a community good article reassessment. If you are interested in the discussion, please participate by adding your comments to the reassessment page. If concerns are not addressed during the review period, the good article status may be removed from the article. AIRcorn (talk) 06:43, 19 January 2020 (UTC)

Padovan sequence source for sum product identity
Hello. It looks like your 24 July 2005 edit to the Padovan sequence page added several identities, including

$$\sum_{m=0}^n P(m)P(m+2)=P(n+2)P(n+3)-1.$$

Can you tell me where you found that, or did you come up with it? I'd like to give an accurate citation in something I'm putting together.

Billionare Boys Club (talk) 18:16, 26 March 2020 (UTC)

PS Please excuse the odd username; it must have been made by someone else using my common email address.


 * I have no idea where I got those identities from. They are not difficult to derive. For example
 * $$P(m+3)P(m+2) - P(m+2)P(m+1) = \left( P(m+3)-P(m+1) \right) P(m+2)=P(m)P(m+2)$$
 * $$\Rightarrow \sum_{m=0}^n P(m)P(m+2) = \sum_{m=0}^n \left( P(m+3)P(m+2) - P(m+2)P(m+1) \right) = P(n+3)P(n+2) - P(1)P(0) = P(n+3)P(n+2) - 1$$


 * Gandalf61 (talk) 14:26, 24 April 2020 (UTC)

Guideline on Medical Advice
You have been a significant contributor to Reference desk/Guidelines. A subordinate set of guidelines is Reference desk/Guidelines/Medical advice. On 9 April 2020 a User took action to demote the Medical Advice document from a guideline to an essay. See the diff. The matter is now under discussion at Wikipedia talk:Reference desk/Guidelines/Medical advice. You may wish to contribute to the discussion. Dolphin ( t ) 13:18, 10 August 2020 (UTC)

Proposed deletion of Van Eck's sequence


The article Van Eck's sequence has been proposed for deletion&#32;because of the following concern: "Relies entirely on primary sources. Not notable; mathematical importance is unclear."

While all constructive contributions to Wikipedia are appreciated, pages may be deleted for any of several reasons.

You may prevent the proposed deletion by removing the notice, but please explain why in your edit summary or on the article's talk page.

Please consider improving the page to address the issues raised. Removing will stop the proposed deletion process, but other deletion processes exist. In particular, the speedy deletion process can result in deletion without discussion, and articles for deletion allows discussion to reach consensus for deletion. Kstern (talk) 01:26, 10 October 2020 (UTC)

Nomination of Van Eck's sequence for deletion
A discussion is taking place as to whether the article Van Eck's sequence is suitable for inclusion in Wikipedia according to Wikipedia's policies and guidelines or whether it should be deleted.

The article will be discussed at Articles for deletion/Van Eck's sequence until a consensus is reached, and anyone, including you, is welcome to contribute to the discussion. The nomination will explain the policies and guidelines which are of concern. The discussion focuses on high-quality evidence and our policies and guidelines.

Users may edit the article during the discussion, including to improve the article to address concerns raised in the discussion. However, do not remove the article-for-deletion notice from the top of the article. –Deacon Vorbis (carbon &bull; videos) 20:20, 15 October 2020 (UTC)

Proposed deletion of Language of mathematics


The article Language of mathematics has been proposed for deletion&#32;because of the following concern: "POV, essay, original synthesis; see talk:Language of mathematics"

While all constructive contributions to Wikipedia are appreciated, pages may be deleted for any of several reasons.

You may prevent the proposed deletion by removing the notice, but please explain why in your edit summary or on the article's talk page.

Please consider improving the page to address the issues raised. Removing will stop the proposed deletion process, but other deletion processes exist. In particular, the speedy deletion process can result in deletion without discussion, and articles for deletion allows discussion to reach consensus for deletion. D.Lazard (talk) 15:22, 21 June 2022 (UTC)

Proposed deletion of Language of mathematics


The article Language of mathematics has been proposed for deletion. The proposed deletion notice added to the article should explain why.

While all constructive contributions to Wikipedia are appreciated, pages may be deleted for any of several reasons.

You may prevent the proposed deletion by removing the notice, but please explain why in your edit summary or on the article's talk page.

Please consider improving the page to address the issues raised. Removing will stop the proposed deletion process, but other deletion processes exist. In particular, the speedy deletion process can result in deletion without discussion, and articles for deletion allows discussion to reach consensus for deletion. Ten Pound Hammer • (What did I screw up now?) 16:14, 21 June 2022 (UTC)

Request bibliographic reference
Hello Gandalf61,

I would like to know a bibliographic reference for a math formula. I found this formula on Wikipedia, but no reference is given.

It's the 2nd formula ($$A(n,k)$$ is an Eulerian number):


 * $$\sum_{k=0}^{n-1}(-1)^k \frac{A(n,k)}{\binom{n-1}{k}}=0, \text{ for  }n > 1$$

in the chapter entitled "Formulas involving alternating sums" on the Wikipedia page:

https://en.wikipedia.org/wiki/Eulerian_number

I've looked at lots of (very complicated...) articles, but there's nothing obvious about this formula. Handbooks of Mathematics, etc. nothing, nothing, nothing...!

I saw that you were one of the contributors to this page. Can you provide a reference?

Thank you. RoyBetthe (talk) 10:12, 14 April 2024 (UTC)