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Prime numbers, diophantine equations, diophantine approximations, analytic or algebraic number theory, arithmetic geometry, Galois theory, transcendental number theory, continued fractions

16 votes
1 answer
2k views

On J. T. Condict's Senior Thesis on Odd Perfect Numbers

I am trying to locate a copy of J. T. Condict's senior thesis on odd perfect numbers: J. Condict, On an odd perfect number's largest prime divisor, Senior Thesis, Middlebury College (1978). I am sur …
Jose Arnaldo Bebita's user avatar
13 votes
2 answers
1k views

Has it been proved that odd perfect numbers cannot be triangular?

(Note: This question has been cross-posted from MSE.) Euclid and Euler proved that every even perfect number is of the form $m = \frac{{M_p}\left(M_p + 1\right)}{2}$ where $M_p = 2^p - 1$ is a prime …
Jose Arnaldo Bebita's user avatar
9 votes
2 answers
759 views

Is there an odd integer $x < 105$ for which it is known that $x \nmid N$, if $N$ is an odd p...

Is there an odd integer $x < 105$ for which it is known that $x \nmid N$, if $N$ is an odd perfect number? I have asked the same question in MSE, but did not get any answers. I was wondering if anyb …
Jose Arnaldo Bebita's user avatar
6 votes
0 answers
503 views

Does the equation $\sigma(\sigma(x^2))=2x\sigma(x)$ have any odd solutions?

This question was posted in MSE in early August 2020. It did garner several upvotes, but did not receive any responses. I have therefore cross-posted it here, hoping that it gets answered. Let $\sig …
Jose Arnaldo Bebita's user avatar
6 votes
3 answers
4k views

Re: Mordell's equation $y^2 = x^3 + k$ and perfect numbers

I have already tried a somewhat exhaustive search of the literature, but couldn't find anything close to the problem that I am working on. My question is: When does Mordell's equation $$Y^2 = X^3 + K$ …
Jose Arnaldo Bebita's user avatar
6 votes
1 answer
2k views

If $N = qn^2$ is an odd perfect number with $\gcd(q,n)=1$, is it possible to have $q + 1 = \...

The title says it all. Question If $N = qn^2$ is an odd perfect number with Euler prime $q$ and $\gcd(q,n)=1$, is it possible to have $q + 1 = \sigma(n)$? Heuristic From the Descartes spoof, with qu …
Jose Arnaldo Bebita's user avatar
5 votes

Algebraic Attacks on the Odd Perfect Number Problem

I agree with Pace - the correct function to consider would be the abundancy index instead of the sigma function itself. In a certain sense, the abundancy index value of 2 for perfect numbers (odd or …
Jose Arnaldo Bebita's user avatar
4 votes
1 answer
1k views

On Sorli's Conjecture Re: OPNs (Circa 2003)

In the PhD dissertation titled "Algorithms in the Study of Multiperfect and Odd Perfect Numbers" (hyperlinked here) and completed in 2003, Ronald Sorli conjectured that the exponent $k$ on the Euler p …
Jose Arnaldo Bebita's user avatar
4 votes
1 answer
334 views

If $N = {q^k}{n^2}$ is an odd perfect number given in Eulerian form, is $n$ a square?

(I have asked a similar question in MSE four days ago, but did not receive any answers. I have therefore cross-posted it to this site, hoping to get some responses.) An odd perfect number $N$ is sai …
Jose Arnaldo Bebita's user avatar
4 votes
2 answers
470 views

On the natural density of almost perfect numbers

This question is pretty basic, so I apologize in advance if it is unsuitable for MO. If so, please do let me know and I will migrate it over to MSE. Essentially, by work of Kanold, we know that the …
Jose Arnaldo Bebita's user avatar
3 votes

Has it been proved that odd perfect numbers cannot be triangular?

Not an answer, but I just want to point out some thoughts that recently occurred to me, which are related to this problem. By this answer, we know that every odd perfect number $N = q^k n^2$ can be w …
Jose Arnaldo Bebita's user avatar
3 votes
0 answers
175 views

Looking for an appropriate reference(s) for two conjectures on odd perfect numbers

(I apologize in advance if this question is unsuitable for MO. If so, please let me know and I will migrate it to MSE.) Let $\sigma(M)$ be the sum of the divisors of the positive integer $M$. For ex …
Jose Arnaldo Bebita's user avatar
3 votes
0 answers
179 views

Does this Theorem 2 from Dandapat et al. imply that $\gcd(\sigma(p^k),\sigma(a^2)) > 1$?

Write the odd perfect number $m=p^k a^2$ as a product of primes $$m = p^k {p_1}^{2a_1} \cdots {p_v}^{2a_v}.$$ (Note that it is known that $v \geq 9$ by work of Nielsen.) Let $N(m)$ be the number of s …
Jose Arnaldo Bebita's user avatar
3 votes

Generalized quasi-perfect numbers

The related equation $$\sigma(n) = An + B(n)$$ where $B(n)$ "is a function that may depend on properties of $n$" is considered in the paper Variations on Euclid’s Formula for Perfect Numbers by Faride …
Jose Arnaldo Bebita's user avatar
3 votes
4 answers
1k views

A conjecture regarding odd perfect numbers

(Note: I asked this question in MSE this June 2018 but did not receive any responses there. I have therefore cross-posted it here, hoping that it gets answered.) Let $\sigma(z)$ denote the sum of t …
Jose Arnaldo Bebita's user avatar

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