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5:08 PM
Jan 12 at 6:05, by Martin Sleziak
I'd guess that the questions tagged divisors+nt.number-theory are all - or at least most of them - tagged incorrectly.
At the moment there are 7 such questions.
3
Q: When is the Wendt binomial circulant determinant divisible by 3?

aorqThe Wendt binomial circulant determinant $W_n$ can be defined quite simply as a resultant: $$ W_n = \operatorname{res}(x^n-1, (x+1)^n-1). $$ Truer to its name, one may also define it as the determinant $\det(A)$ of the circulant matrix with entries $A_{i,j} = \binom{n}{\lvert i-j\rvert}$. The We...

7
Q: Is $n=6$ the only integer satisfies ${\sigma}_x(n) \equiv 0\bmod{n}$ for every odd integer $x > 0$ and $2 (\bmod n)$ if $x$ is even integer?

zeraoulia rafikAfter a few computations in wolfram alpha about the divisor function for some values of $n$ to look the behavior of $\sigma_x(n)\bmod n$ for $\,n=6,\,$ i got this result : $\sigma_x(6)=0 \bmod 6$ for $x$ odd and 2 mod 6 if $x$ is even Edit:01 :${\sigma}_x(n) =\sum_{d|n} d^x$ is the sum divisor ...

0
Q: Is there an example of integers ($x,p, q ,y$ ) which satisfies the below conditions in this claim?

zeraoulia rafikEdit 01:In order to look divisibility among power divisor function where i would like to know if there a such integer $n>1 $ with y coprime to $x$ then we have: :$\sigma_y(n)\bmod \sigma_x(n)=0$, by wolfram alpha i have got no integer n>1 satisfies the equation $\sigma_y(n)\bmod \sigma_x(n)=0$ ...

1
Q: Is $n=5$ the only integer satisfy the equation :$\sigma((n-1)!+1))=\sigma(n²)$?

zeraoulia rafikReally i'm interesting to check solutions of equations which it is related to sum divisor function .I accrossed the below equation which i got only one integer solution using wolfram alpha as shown here. My question here: Is $n=5$ the only integer satisfy the equation :$\sigma((n-1)!+1))=\sig...

-2
Q: Is it possible to show that :for $n \geq 1:\sigma(n!-1) $ never be prime and why $\sigma(n!-1)\bmod 10 $ at most is $0$?

Youssra El Yossra YoussraThis question is related to my question here , I w'd like to check if $n \geq 1:\sigma(n!-1) $ never be prime according to some computations which i did in wolfram alpha to come up with parity of sum power divisor function at $n!-1$ for some integer $n$ i observed that $\sigma(n!-1)\bmod 10 $ at ...

6
Q: When is $ \sigma(n!-1) $ a perfect square?

Youssra El Yossra YoussraI am looking for pairs of positive integers $(m,n)$ such that $ \sigma(n!-1) =m^2$, where $\sigma$ is the sum of divisors function. Examples occur with $(m,n)=(12,5),(1,2)$. Question: Are there others?

3
Q: Bound on the number of primitive divisors of the $n$th Fibonacci number

user40023It is a result of Carmichael that for any integer $n > 12$, the Fibonacci number $F_n$ has at least one primitive divisor, that is, a prime factor $p$ such that $p$ does not divide any $F_m$ with $1 \leq m < n$. Indeed, a more general result for all Lucas and Lehmer sequences has been proven by B...

I suppose some users simply do not notice the tag-excerpt.
 
5:26 PM
0
A: Help improve tagging!

Martin SleziakI suggest to rename the tag divisors in a way which distinguishes it more clearly from divisor-multiples. The tag-info for divisors clearly says: For questions related to divisors in the sense of algebraic geometry (Cartier divisors, Weil divisors and so on). For question on divisors in the ...

 
in Homotopy Theory, 7 mins ago, by Martin Sleziak
What do you think the about renaming divisors tag in a way which makes clearer that it is not about divisibility of numbers? I have just made a post on meta about this. Any feedback there or in MO editors' lounge is more than welcome.
 
5:40 PM
I considered whether to make a separate question about this or whether to post it in the long thread as an answer.
But most likely there won't be that much discussion about this. (In general tag-related issues do not attract that much attention these days.)
Answers might be more comfortable way to suggest alternative names for the tag. But I suppose comments will suffice for this purpose.
 

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