Talk:Euler numbers

Euler

Wierd:

The even-indexed Euler numbers (except E0) are all zero. Some other values are: E0 = 1 E2 = -1 E4 = 5 ...

Random Comment

"Can we have little more explanatiion for this number.. may be by some examples.. This si not very clear.." I removed this from the article. --Antonio.sierra 02:44, 25 August 2007 (UTC)

Interwikis

Help would be appreciated in watching the interwikis. Many interwikis lead to articles that were in fact about the number e (mathematical constant). They were removed with help from some other people from the Dutch wikipedia, but it would be good to watch any interwiki that is added to this page to see if they go to correct article. Thanks, LeRoc (talk) 16:47, 6 May 2008 (UTC)

disambiguation needed

This topic is not actually the primary one associated to the phrase "Euler number". For example, if you query Google Scholar, you will see many hits for Euler number coming from topology (Euler number of bundle, Euler characteristic, etc.). Comments? --C S (talk) 17:16, 23 July 2008 (UTC)

Can someone clarify the sum over partitions section?

I am not very familiar of the notation used in the sum over partitions section. Can an expert may the notation easier to understand or at least reference the notations used? Thanks. — Preceding unsigned comment added by Davikrehalt (talk • contribs) 18:04, 3 March 2013 (UTC)

External links modified

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Congruences

Congruences of the Euler numbers have a long history! In 1910, Frobenius already showed the result as a special case that

$E_{p-1}\equiv \textstyle {\begin{cases}0\mod p&{\text{if }}p\equiv 1{\bmod {4}};\\2\mod p&{\text{if }}p\equiv 3{\bmod {4}}.\end{cases}}$

See https://zbmath.org/1264.11013 for reference. — Preceding unsigned comment added by 2A02:8108:96BF:E2A4:257C:E626:C5AB:8D98 (talk) 22:48, 10 January 2025 (UTC)

Euler number/characteristic confusion

I have proposed adding Euler characteristic to the "not to be confused with" section. Colloquially, these are often called "Euler numbers" and I have seen other cohomological invariants being formally related to power series expansions (like the Todd class) so I did not think it was unreasonable for Euler numbers to be related to "Euler numbers/characteristics." However, there is some disagreement about how plausible confusion this is from @JayBeeEll. Does anyone have an external suggestion? AndyrooP (talk) 18:37, 30 April 2026 (UTC)

Well, I guess that one might put together "Möbius number" (which is an Euler characteristic of the order complex of a poset) and "Euler characteristic" and wind up at Euler number. No strong opinion, however. Russ Woodroofe (talk) 22:31, 30 April 2026 (UTC)