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16 votes
0 answers
787 views

Numbers of the form $x^2(x-1) + y^2(y-1) + z^2(z-1)$ with $x,y,z\in\mathbb Z$

Roger Heath-Brown conjectured that any integer $k\not\equiv\pm4\pmod9$ can be expressed as $x^3+y^3+z^3$ with $x,y,z\in\mathbb Z$ in infinitely many different ways. Also it is well-known that some ...
Alkan's user avatar
  • 701
15 votes
0 answers
365 views

Do primes of the form $4k+1$ ever lead the greatest prime factor race?

Analogous to Chebyshev's race between primes, I examined the race between primes in the greatest prime factors, GPF, of natural numbers. Similar to the regular prime race, in the GPF race, the ...
Nilotpal Kanti Sinha's user avatar
10 votes
0 answers
598 views

Does the interior of Pascal's triangle contain three consecutive integers?

This question defeated Math SE, so I am posting it here. Consider the interior of Pascal's triangle: the triangle without numbers of the form $\binom{n}{0},\binom{n}{1},\binom{n}{n-1},\binom{n}{n}$. ...
Dan's user avatar
  • 3,527
10 votes
0 answers
4k views

Is the conjecture A+B=C following correct?

Is the conjecture on A+B=C following correct ? Conjecture: Let $A, B, C$ be three positive integer numbers such that $A+B=C$ with $\gcd(A, B, C) = 1$. By Fundamental theorem of arithmetic we write: $...
Đào Thanh Oai's user avatar
8 votes
0 answers
346 views

A generalization of Feit–Thompson conjecture, for square-free integers

I asked the following question with my account that I have for these sites Mathematics Stack Exchange and MathOverflow. The bounty that I offered in MSE expired without answers. The post that I refer ...
user142929's user avatar
8 votes
0 answers
257 views

Order of magnitude of extremely abundant numbers and RH

I have always been intrigued by the fact that Riemann's hypothesis is equivalent to the assertion (you can find the scanned paper here) that the inequality $$\frac{\sigma(n)}n<e^\gamma \log\log n \...
Wolfgang's user avatar
  • 13.4k
6 votes
0 answers
506 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 $\...
Jose Arnaldo Bebita's user avatar
5 votes
0 answers
192 views

Heuristics for the very little torsion in the cohomology of Shimura variety

Consider the following statement which is a part of Conjecture 1.3 in the paper titled "The asymptotic growth of torsion homology for arithmetic groups" authored by N. Bergeron and A. ...
random123's user avatar
  • 443
5 votes
0 answers
614 views

is there a link with the probabilistic model for prime numbers?

Let $x \in \mathbb{R}_+$ and $k \in \mathbb{N}^{*}$. Let : $$\mathcal{A}(x)=\#\{(a_1, a_2, \ldots, a_k) \in \mathbb{P}^k \mid (a_1, a_2, \ldots, a_k \text{ verifying some properties}) \, , a_k \...
Lagrida Yassine's user avatar
5 votes
0 answers
238 views

The set of numbers $a+b$ such that $ma^2+nb^2$ is prime

Conjecture: If $m,n$ are coprime it exist a minimal natural number $N_{mn}$ such that: $\{a+b>N_{mn}\mid a,b\in\mathbb N^+\wedge ma^2+nb^2\in\mathbb P_{>2}\} = \{ k > N_{mn} \mid \...
Lehs's user avatar
  • 862
5 votes
0 answers
425 views

Conjectured new primality test for Mersenne numbers

How to prove that this conjecture about a new primality test for Mersenne numbers is true ? Definition: Let $M_{q}=2^{q}-1 , S_{0} = 3^{2} + 1/3^{2} , \ and: \ S_{i+1} = S_{i}^{2}-2 \pmod{M_{q}}$ ...
Tony Reix's user avatar
  • 161
4 votes
0 answers
317 views

there exist infinite many $n\in\mathbb{N}$ such that $S_n-[S_n]<\frac{1}{n^2}$

Let $S_n:=1+\frac12+\frac13+\ldots+\frac1n$. Is it true that the set of $n\in\mathbb N$ such that $$S_n-[S_n]<\dfrac{1}{n^2}$$ is infinite? Here, $[x]$ represents the largest integer not exceeding $...
math110's user avatar
  • 4,280
3 votes
0 answers
327 views

Conjecture about primes and Fibonacci numbers

I posted this conjecture on math.stackexchange, but I received no answer proving or disproving it: if $ m > 4 $ is a positive integer not divisible by $ 2 $ or $ 3 $, it's ever possible to find a ...
user967210's user avatar
3 votes
0 answers
252 views

Counting twin primes with a sieve-like algorithm

The sequence A002822, denoted as $S$, represents all the twin primes except $\{3, 5\}$. Other than that exception, $k$ and $k+2$ are twin primes iff $(k+1)/6\in S$. Let $S(N)$ be the subset of $S$ ...
Vincent Granville's user avatar
3 votes
0 answers
177 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 ...
Jose Arnaldo Bebita's user avatar
2 votes
0 answers
113 views

On a subset of the $abc$ triples

The $abc$ conjecture states that, for every positive real $\varepsilon$, there exist only finitely many triples $(a, b, c)$ of coprime positive integers such that $a + b = c$ and $$c > \...
Olivier Rozier's user avatar
2 votes
0 answers
300 views

How soon can we represent a number as the sum of two primes?

Posting in MO since it was unanswered in MSE. Goldbach's conjecture says that every even number can be represented as the sum of two primes. But how soon can we find such a representation. Taking $20 =...
Nilotpal Kanti Sinha's user avatar
2 votes
0 answers
269 views

A relation of the prime counting function $\pi$ to counting the ordered ways of a number $n$ as a sum of two primes and two questions?

The definitions are from these two questions: https://math.stackexchange.com/questions/3164216/a-series-related-to-prime-numbers https://math.stackexchange.com/questions/4349186/trying-to-understand-...
mathoverflowUser's user avatar
2 votes
0 answers
114 views

A conjectured upper bound for the mean value of prime divisors inside prime gaps

In 1969 C.A. Grimm stated this interesting conjecture: the prime gap $\,G_n=\{x\in N:p_n\lt x\lt p_{n+1}\}\,$ contains at least $\,\#G_n=(p_{n+1}-p_n)-1=g_n-1\,$ distinct prime divisors, that is if $\,...
Augusto Santi's user avatar
2 votes
0 answers
244 views

Weak Leopoldt Conjecture for the Split Prime $\mathbb{Z}_p$-extension

In his 1973 Annals paper, Iwasawa proved that the weak Leopoldt Conjecture holds for the cyclotomic $\mathbb{Z}_p$-extension of any number field. If $K$ is an imaginary quadratic field and $F/K$ is ...
debanjana's user avatar
  • 1,283
2 votes
0 answers
617 views

Arithmetic progression and average of two prime numbers

Let $A=(a_n : n \in \mathbb{N})$ be the sequence given by: $$ \ a_n = a_1 + (n - 1)d,\quad a_1,\ d,\ n \in \mathbb N,\quad d\gt a_1,\quad \gcd(a_1,\ d)=1. $$ For all terms of $A$ greater than $\ \...
Mike's user avatar
  • 359
1 vote
0 answers
77 views

Conjecture about Euler quotients related to non-Wieferich numbers $W(n)=\frac{2^n+1}{3}$

For odd natural $n$ define the Euler quotient: $$ a(n)=\frac{(2^{\phi(n)}-1) \bmod n^2}{n}=\frac{2^{\phi(n)}-1}{n} \bmod n$$ $a(n)=0$ is $n$ being Wieferich number (not necessarily prime). For odd $n$,...
joro's user avatar
  • 25.4k
1 vote
0 answers
152 views

A new Conjecture at OEIS sequence A376842

Here is a new conjecture of mine from the appendix of an unpublished manuscript currently under review. Let $b \in \mathbb{Z}^+$ and assume that $n$ is an integer greater than $1$ and not a multiple ...
Marco Ripà's user avatar
  • 1,451
1 vote
0 answers
158 views

Initial conditions to falsify Rowland's conjecture

Based on the Rowland's paper (A natural prime-generating recurrence), is there any theorem to show that for which initial condition $a(1) = k$ the conjecture can be falsified? For example, for $k$ ...
OmG's user avatar
  • 151
1 vote
0 answers
47 views

On quasiperfect numbers, $\operatorname{rad}(\sigma(n))=\operatorname{rad}(2n+1)$ and $\operatorname{rad}(\sigma(n)-1)=\operatorname{rad}(2n)$

An integer $n\geq 1$ is said quasiperfect number if the sum of its positive divisors $\sigma(n)$ is equal to $2n+1$. See the Wikipedia Quasiperfect number. The idea of this post is ask about the ...
user142929's user avatar
1 vote
0 answers
222 views

Attempt of exploit the equation $1/\operatorname{rad}(n)=1/2-2\varphi(n)/\sigma(n)$ in the context of even perfect numbers, and a related conjecture

It is well known that the problem concerning even perfect numbers is to prove or refute if there are infinitely many of them. Few weeks ago I wrote the following conjecture, where $\varphi(n)$ denotes ...
user142929's user avatar
1 vote
0 answers
119 views

If $N = q^k n^2$ is an odd perfect number, and $n < q^{k+1}$, does it follow that $k > 1$?

Let $N = q^k n^2$ be an odd perfect number with Euler prime $q$. According to Dickson (as pointed out recently by Beasley), Descartes conjectured $k=1$ in a letter to Mersenne in 1638, with Frenicle'...
Jose Arnaldo Bebita's user avatar
0 votes
0 answers
241 views

Conjecture about some recurrent primes

I want to know if there are conjectures similar to this one, I know there is the Bell primes conjecture or Gardner conjecture (mentioned in this page https://en.wikipedia.org/wiki/Bell_number), but ...
Abdelhay Benmoussa's user avatar
0 votes
0 answers
374 views

Is the Conjecture of Representing Integers as Differences of Semiprimes and Primes Extendable to Products of Distinct Primes?

Conjecture: Let $k$ and $l$ be fixed distinct positive integers ($k≠l$). Then, for every positive integer $n$, there exist prime numbers $p_1,p_2,…,p_k∈\mathbb{P}$ and $q_1,q_2,…,q_l∈\mathbb{P}$ such ...
Akira Sukigi's user avatar
0 votes
0 answers
82 views

Inequalities $\pi(x^a+y^b)^\alpha\leq \pi(x^c)^\beta+\pi(y^d)^\gamma$ involving the prime-counting function, where the constants are very close to $1$

Let $\pi(x)$ be the prime-counting function, I'm curious about if a suitable variant of the second Hardy–Littlewood conjecture (this corresponding Wikipedia) $$\pi(x^a+y^b)^\alpha\leq \pi(x^c)^\beta+\...
user142929's user avatar