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On an inequality for the arithmetic function counting the number of primes $\lfloor n^c\rfloor$ in the spirit of Ramanujan's prime counting inequality

In page 3 of [1] (please see if you need it the book by Berndt) Axler refers an inequality that involves the prime-counting function $\pi(x)$ and that was deduced by Ramanujan. I'm curious to know if ...
user142929's user avatar
2 votes
0 answers
243 views

Primes in arithmetic progression

We call a prime $p$ "good" if there is $0<k<\log p$ with $2kp+1$ prime. What is the asymptotic density of good primes?
Emmanuel Guillemin's user avatar
5 votes
0 answers
349 views

Smallest prime $p$ such that $2\mid\operatorname{ord}_p(q)$, the multiplicative order of $q$ modulo $p$

$\DeclareMathOperator\ord{ord}$Let $q$ be prime. I want to upper bound the smallest odd prime $p$ such that $2\mid\ord_p(q)$ (where $\ord_p(q)$ is the multiplicative order of $q$ modulo $p$). Using ...
Tejas Rao's user avatar
  • 101
13 votes
1 answer
777 views

Large sieve inequality for sparse trigonometric polynomials

Let $S(\alpha) = \sum_{n\leq N}f(n) e^{2\pi i \alpha n}$ for some arithmetic function $f$. Suppose $\alpha_1, \ldots, \alpha_R$ are real numbers that are $\delta$-spaced modulo $1$, for some $0 < \...
user152169's user avatar
1 vote
0 answers
103 views

$g$-gap radius of an integer

For $n$ a large enough composite integer, define the $g$-gap radius of $n$, if it exists, for positive even $g$ as the smallest positive integer $\rho_{g}(n)$ such that both $n-\rho_{g}(n)$ and $n+\...
Sylvain JULIEN'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
154 views

Reference request for the following results

I am looking for references on the following results. In what follows $\pi(x)$ denotes the prime counting function. Result 1. For all real $k>1$ there exists $x^k_0 \in \mathbb{R}$ such that for ...
S. Das's user avatar
  • 31
8 votes
1 answer
471 views

Conjecture about the density of primes

Conjecture For any sufficiently large integer $kn$ , the sequence representing the number of primes in each block obtained by splitting $kn$ into $k$ equal blocks, is a strictly decreasing sequence, ...
François Huppé's user avatar
6 votes
0 answers
149 views

Dickson's conjecture for Beatty sequences

A particular case of Dickson's Conjecture states that for $a_1,q_1,a_2,q_2$ with $(a_1,q_1)=(a_2,q_2)=1$, there are infinitely many $n$ for which $q_1 n + a_1$ and $q_2 n+a_2$ are both prime, provided ...
Joshua Stucky's user avatar
2 votes
1 answer
224 views

Prime factor distribution over $\mathbb{N}$

I wonder if there is something like a general "prime component distribution pattern" of "the general natural number" $n$? Using the following notation for the prime factorization $...
Raphael J.F. Berger's user avatar
3 votes
1 answer
329 views

Fully explicit Linnik's Theorem

Linnik's Theorem states that there exist absolute constants $c$ and $L$ such that for every $m \in \mathbb{N}$ and every $a$ coprime to $m$, there is a prime $p$ with $p \equiv a \pmod{m}$ and $p < ...
Woett's user avatar
  • 1,663
-4 votes
1 answer
229 views

A generalization Bertrand's postulate [closed]

Let $n, k$ are integers number such that $1<n \le k$, does always exist a prime number between $kn$ and $k(n+1)$? When $n=1, k>1$ always exist a prime number between $k$ and $2k$ the question ...
Đào Thanh Oai's user avatar
6 votes
2 answers
723 views

Does always exist a prime number between $n(n+1)$ and $(n+1)(n+2)$?

Let $n$ is positive integer number, does always exist a prime number between $n(n+1)$ and $(n+1)(n+2)$?
Đào Thanh Oai's user avatar
-3 votes
1 answer
271 views

Is this Goldbach conjecture related quantity equal to the number of Goldbach decompositions up to a bounded quantity?

This question is a follow-up to About Goldbach's conjecture and as such deals with the notion of primality radius of a composite integer $n$, that is, a positive integer $r$ such that both $n-r$ ...
Sylvain JULIEN's user avatar
6 votes
0 answers
654 views

Generalized prime number theorem and Riemann Hypothesis for non-number math objects

My question is about some math objects (matrices, polynomials) and operators that satisfy a number of properties which can lead to a theory similar to PNT, RH, Dirichlet functions, abscissa of ...
Vincent Granville's user avatar
5 votes
0 answers
205 views

Is there a polynomial version of Wilson's theorem which can avoid Cramer flavored conjectures?

Wilson's theorem states that a natural number $n > 1$ is a prime number if and only if the product of all the positive integers less than $n$ is one less than a multiple of $n$. Is there a version ...
Turbo's user avatar
  • 13.9k
2 votes
0 answers
205 views

Sum of all primes below $n$ without listing all primes below $n$

Asymptotically there is around $\frac{n}{\ln n}$ primes below a given integer $n$. Thus $\frac{n}{\ln n}$ is a lower bound for the time complexity of any algorithm that at some point finds each prime ...
vlben's user avatar
  • 21
3 votes
1 answer
134 views

Is it possible to find an estimate of $\sum_{k=1}^n\frac1{\varphi(k\cdot p_k)}$?

Is it possible to find an estimate of the summation $$s(n)=\sum_{k=1}^n\frac1{\varphi(k\cdot p_k)}$$ where $\varphi(n)$ is the totient function and $p_k$ the k-th prime? The corresponding series seems ...
Augusto Santi's user avatar
7 votes
1 answer
635 views

Is there a Chebotarev‘s theorem for non-Galois extension over Q?

For a Galois extension $K/\mathbb{Q}$, the Chebotarev Density Theorem predicts the density of primes with a certain splitting type. I'm wondering if there is a similar result for non-Galois extension? ...
Yuan Yang's user avatar
  • 547
3 votes
1 answer
247 views

Explicit bounds on number of squarefree numbers coprime to a certain number

We know that the number of squarefree integers $\le x$ that are coprime to $A$ is $$ Q_A(x) = x \prod_{p|A} \left(1-\frac{1}{p}\right) \prod_{p \nmid A} \left(1-\frac{1}{p^2}\right) + O(\sqrt{x}). $$ ...
Iguana's user avatar
  • 301
20 votes
1 answer
1k views

Possible contemporary improvement to bounded gaps between primes?

In his summary of his book Bounded gaps between primes: the epic breakthroughs of the early 21st century, Kevin Broughan writes Which brings me to my final remark: where to next in the bounded gaps ...
David Roberts's user avatar
  • 35.5k
0 votes
0 answers
50 views

k specific prime factors guess and related prime guess [duplicate]

there is no more than one group of continuous composite sequence of length k composed of only k different specific prime factors. for example 2 3 5[8 9 10]just only one group. I have prove that k ...
光子精灵S's user avatar
8 votes
1 answer
937 views

On the connection between sums of prime numbers and distribution of prime numbers

As an amateur mathematician, I have always been fascinated by the magic of prime numbers, and their apparently random distribution. I was utterly amazed when I found the following connection between ...
Juan Moreno's user avatar
-1 votes
1 answer
279 views

A question on assigning finite values to divergent sums involving expression of primes

We know the following: $$\gamma=\lim_{n\to\infty }\left(\sum_{k=1}^n\frac{1}{k}-\ln(n)\right).$$ This could be a good candidate for renormalized sum of $\left(\sum_{k=1}^{\infty}\frac{1}{k}\right)$. ...
Zaza's user avatar
  • 149
1 vote
1 answer
342 views

What is a non-trivial upper bound on the $k$th prime below a given prime $p$?

Given a prime number $p_0$, by Bertrand's postulate we know that \begin{gather} p_1\ge\frac{p_0}{2}\\ p_2\ge\frac{p_1}{2}\ge\frac{p_0}{2^2}\\ \vdots\\ p_k\ge\frac{p_0}{2^k} \end{gather} where $p_1,p_2,...
Martund's user avatar
  • 113
1 vote
0 answers
96 views

Smooth number pairs satisfying a congruence

Let $\mathcal P=\{p_1,\dots,p_{2t}\}$ be $2t$ primes between $2^\ell$ and $2^{\ell+1}$ and fix an exponent bound $a\in\mathbb Z_{\geq2}$. Fix $N\in\mathbb N$ whose prime factors $p$ satisfy $p>2^{\...
Turbo's user avatar
  • 13.9k
-1 votes
1 answer
125 views

Prove using Dyck naturals: for $n \in \mathbb{N}_{+}$ and big enough $k \in \mathbb{N}_{+}$, $p_{k-1} < \cdots < np_{k-a_{n}}$ (a is A073093)

While conducting research in connection with arXiv:2102.02777 ("Recursive Prime Factorizations: Dyck Words as Numbers"), I noticed certain interesting patterns, one of which inspired the ...
JustAsking's user avatar
10 votes
1 answer
694 views

Set of prime numbers $q$ such that $\sum\limits_{p\leq\sqrt{q}}p=\pi(q)$, where $p$ are prime numbers

The question is: does the set of prime numbers $q$ such that $\sum\limits_{p\leq\sqrt{q}}p=\pi(q)$, where $p$ are prime numbers, contain infinitely many elements? You can find the first elements here (...
Juan Moreno's user avatar
0 votes
0 answers
118 views

Primes in many variables polynomials form

As in this question >> Primes of the form $x^2 + y^2 + 1$ There are $\asymp \dfrac{x}{\log^{3/2} x}$ primes of the form $a^2+b^2+1$ up to $x$. I read a book stated that there exist a polynomial $...
W. Wongcharoenbhorn's user avatar
0 votes
1 answer
249 views

How differently would we model the distribution of primes if prime gap is larger?

Cramer's conjecture based on his random model provides prime gaps are bound by $O(\log^2p_n)$ where the gap is between $(n+1)$th and $n$th prime. How differently would primes be modeled if gaps of $O(...
Turbo's user avatar
  • 13.9k
0 votes
0 answers
99 views

On a generalised result of Mertens

Let $\varphi$ be the Euler totient function, $N_k$ denote the product of the first $k$ primes and define $$f(k, r) = \frac{(N_k)^r}{\varphi((N_k)^r) \log \log ((N_k)^r)}.$$ where $r \in \mathbb{N}$. ...
Q_p's user avatar
  • 1,019
0 votes
1 answer
137 views

Search for gaps between primes where each composite is divisible by increasing integers (2, 3, 4, ...)

Almost every text of number theory contains in its first chapters something similar to the following: For any integer n, the factorial n! is the product of all positive integers up to and including n....
Augusto Santi's user avatar
1 vote
0 answers
81 views

An upper bound for $\,m_k=\min\,\{m\in N:\,mp_k+1\;\;is\;prime\}$

For each prime $p_k$ one can define $$m_k=\min\,\{m\in N:\,mp_k+1\;\;is\;prime\}$$ Some computations suggest that $$m_k=O\Big(\frac{2\sqrt k}{\log k}\Big)$$ Is this estimate confirmed by analytic ...
Augusto Santi's user avatar
2 votes
0 answers
54 views

Asymptotic growth of the collection of Miller-Rabin pseudo-primes witnessed by a set

Consider a set $S$ of positive integers[*]. Define $P(S)$ as the set of numbers $N$ for which elements of $S$ are "witnesses" for the Miller-Rabin test for primality of $N$. Explicitly $P(S)=...
Kapil's user avatar
  • 1,566
-1 votes
1 answer
258 views

A number theoretical identity of exponential sum

I try to understand a number theoretical identity used by Jan-Christoph Schlage-Puchta in this answer. He defined the function $$S(\alpha)=\sum_{n\leq N}\Lambda(n) e(n\alpha)$$ where $\Lambda(n)$ is ...
user267839's user avatar
  • 6,018
0 votes
1 answer
191 views

Are there some results which count $\sum_{p\in [x/2,x]} \log p$ or $\sum_{p\in [x,y]} \log p$ for for $x$ and $y$ positive and real?

I have seen the prime number theorem and on the of versions I know is that $\sum_{p\leq x} \log p=O(x)$ (I am counting over primes here and in the rest of the post). Are there any similar results for ...
user avatar
2 votes
0 answers
313 views

Proving that the Riemann zeta function is zero free on Re=1 using the prime number theorem

Is $\frac{-\zeta'(s)}{\zeta(s)}+\frac{-s}{s-1}$ an analytic continuation, holomorphic for $Re\ s > 0,\ s\neq 1$, of $f(s)=s\int_{1}^{\infty}\frac{\psi(x)-x}{x^{s+1}}\mathrm{d}x$? If so: Let $s_{0}$ ...
Juu's user avatar
  • 129
2 votes
0 answers
94 views

How far ahead do we have to look after $p_n$ to be sure we find another prime $q$ such that $(p_n+q)/2$ is also prime?

If Goldbach's conjecture is true, given a prime $p_n$ is surely possible to find another prime $q$ such that $\frac{p_n+q}2$ is also prime. But I ask: how far ahead do we have to look after $p_n$ to ...
Augusto Santi's user avatar
2 votes
1 answer
273 views

Primes in modular arithmetic progression

Fix a prime $p$. I want to get $k<p$ primes $p_1<\dots<p_k$ such that at every $i\in\{1,\dots,k\}$ we have $$p_i\equiv (2i+1+c)\bmod p$$ where $c$ is fixed and $2k+1+c<p$ holds. For a ...
Turbo's user avatar
  • 13.9k
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
4 votes
1 answer
395 views

Mertens formulas aren't enough for prime number theorem

For the primes it's true that $$ \sum_{p \le x}\frac{1}{p} = \ln\ln x + M + O(1/\ln x) $$ where, $M$ is suitable constant, and, moreover, the prime number theorem gives that $$ \lim_{x\to\infty}\frac{\...
user627482's user avatar
7 votes
2 answers
636 views

How to use the Prime Number Theorem in order to prove Selberg's Formula?

I`m reading Melvin B. Nathanson's "Elementary Methods in Number Theory" and I can't think of a way of deducing Selberg's formula (9.3) from the prime number theorem. This is one of the tasks ...
Juu's user avatar
  • 129
4 votes
1 answer
310 views

Question on an analytic number theory paper

My question is just a ``I don't understand what goes on in X of paper Y" so I don't know if I can post it; on the other hand it is research. I posted it in stackexchange but it received no ...
tomos's user avatar
  • 1,381
2 votes
0 answers
422 views

Sequences with high densities of primes: how to boost them to get even more and larger primes

I propose a methodology to help find large prime numbers with a much higher probability than picking up random numbers and testing them for primality. This would help speed up prime number generators ...
Vincent Granville's user avatar
3 votes
1 answer
225 views

What are the best known bounds for the smallest primes larger than $n$?

Let $n>1$ be some integer. Define $p, q$ to be the smallest primes larger than $n$, where $p<q$. What are the best known effective lower and upper bounds for $p$ and $q$ ?
user avatar
4 votes
1 answer
2k views

Bounds for prime counting function

The prime counting function $\pi(x)$ is defined as \begin{equation} \pi(x)=\sum_{p\leq x}1 \end{equation} where $p$ runs over primes. I have seen many bounds for $\pi(x)$ such as \begin{equation} \...
russian bot's user avatar
3 votes
0 answers
147 views

The bias of consecutive prime numbers towards being incongruent modulo 3

Given a positive integer $n$, let $f_1(n)$ denote the number of pairs of consecutive prime numbers $\leq n$ which are incongruent modulo 3, and let $f_2(n)$ denote the number of pairs of consecutive ...
Stefan Kohl's user avatar
  • 19.6k
24 votes
1 answer
2k views

Parity of the multiplicative order of 2 modulo p

Let $\operatorname{ord}_p(2)$ be the order of 2 in the multiplicative group modulo $p$. Let $A$ be the subset of primes $p$ where $\operatorname{ord}_p(2)$ is odd, and let $B$ be the subset of primes $...
Shahab's user avatar
  • 429
13 votes
1 answer
383 views

Numbers that don't start with (p-1) in base p for any p

Say that an integer $n$ is $p$-leading if its expansion in base $p$ starts with the digit $p-1$. My postdoc, Lifan Guan, asks: are there infinitely many positive integers $n$ that are not $p$-leading ...
H A Helfgott's user avatar
  • 20.2k
1 vote
1 answer
327 views

Symmetry in Hardy-Littlewood k-tuple conjecture

Assuming Hardy-Littlewood $k$-tuple conjecture, do the "dual" prime constellations $(0,h_1, h_2,\cdots, h_i,\cdots, h_{k-1}=d)$ and $(0, h_{k-1}-h_{k-2}, h_{k-1}-h_{k-3},\cdots,h'_i=h_{k-1}-...
Sylvain JULIEN's user avatar

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