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About Omega prime function

Let $ω(n)$ be the number of distinct prime factors of $n$. Is the inequality $ω(n)\leq C\log\log(n)$ true and if so what is the value of the constant $C$ ?
Omega's user avatar
  • 31
0 votes
0 answers
91 views

How to use prime number theorem In such cases?

Let, $$A(x)=\sum_{p\leq x}f(p)$$ Where $p$ is a prime number. Under the Prime Number theorem we have that, $$\pi(x)=Li(x)+O\left(\frac{x}{e^{a\sqrt{\ln(x)}}}\right) $$ as $x$ approach infinity. Now, $$...
RAHUL 's user avatar
  • 111
0 votes
0 answers
80 views

Relevance of the deduction of similar theorems than Maier's theorem for other prime constellations

A year ago I asked this question on Mathematics Stack Exchange with identifier 4245823 and same title Relevance of the deduction of similar theorems than Maier's theorem for other constellations of ...
user142929's user avatar
3 votes
1 answer
348 views

On conjectures about the arithmetic function that counts the number of Sophie Germain primes

I've edited this post two years ago on Mathematics Stack Exchange, with identifier 3590406 and same title On conjectures about the arithmetic function that counts the number of Sophie Germain primes, ...
user142929's user avatar
1 vote
0 answers
482 views

Explicit formula for zeta function with special type of weight

Consider the following line of thinking: $$\pi(x) = \operatorname{R}(x) - \sum_{\rho}\operatorname{R}(x^{\rho}) - \frac1{\ln x} + \frac1\pi \arctan \frac\pi{\ln x} $$ Here, $\operatorname{R}(x) = \...
TPC's user avatar
  • 782
2 votes
0 answers
244 views

Lower bounding the number of Galois radii of an integer

Recall that I call $r>0$ a Galois radius of an integer $n$ if $n-r=p^a$ and $n+r=q^b$ with $p$ and $q$ primes and positive $a$ and $b$ and a primality radius of $n$ if $a=b=1$. Does it suffice to ...
Sylvain JULIEN's user avatar
11 votes
2 answers
1k views

Do consecutive integers have a big prime factor?

Let us say that three consecutive positive integers $(m-1,m,m+1)$ have a big prime factor if the largest prime factor $p$ of $N=(m-1)m(m+1)$ satisfies $e^p>N$. I ckecked that it is true for all $m&...
Sebastien Palcoux's user avatar
0 votes
0 answers
89 views

A similar inequality for the Dedekind psi function, than an inequality stated by Schinzel

I would like to ask about the next question that seems to me interesting. I know an article that was written by Andrzej Schinzel in which he stated Lemma 2. In this post we denote the Dedekind psi ...
user142929's user avatar
-1 votes
1 answer
250 views

Significance of $N_0(T+1)-N_0(T)\sim \frac{1}{2\pi}\log \frac{T}{2\pi}$

Let $N(T)$ be the number of zeros of Riemann zeta function upto height $T$ in the critical strip and $N_0(T)$ be the number of zeros on the critical line. What will be the significance of proving ...
user avatar
2 votes
0 answers
263 views

Selberg's 1943 result on primes in short intervals and primality radius

This preprint: https://arxiv.org/abs/2207.05038 states in the last paragraph of the first page that a result of Selberg (1943) implies that under RH, almost all intervals of the form $(x,x+\left(\log ...
Sylvain JULIEN's user avatar
9 votes
1 answer
422 views

Getting prime by changing 2 digits

I just got a result, an exercise of Tenenbaum's book that one cannot get a prime from arbitrary natural number $n$ by changing only one digit of its decimal expansion. For example, you cannot get ...
Laurence PW's user avatar
5 votes
1 answer
611 views

Why does this convolution of the prime counting function $\pi$ look like a parabola?

In this previous question it is shown that the convolution of the prime counting function $\pi$ with itself, is related to the Goldbach conjecture: $$\pi^*(n):=\sum_{k=0}^n \pi(k) \pi(n-k)$$ The ...
mathoverflowUser's user avatar
2 votes
0 answers
158 views

Quadratic patterns in summands of Goldbach's conjecture

Let $n $ be even and define $$ Q(n)=\sum_{\substack{ p,q \ \textrm{ primes} \\p+q=n }}\left(\frac{p}{q} \right),$$ where $\left(\frac{p}{q} \right)$ is the quadratic Legendre symbol. Has this sum been ...
Dr. Pi's user avatar
  • 3,062
2 votes
0 answers
125 views

Conditional stronger bounds on Linnik theorem with prime power modulus

This post is related to questions asked here and here. However, I include the relevant background on least prime in arithmetic progressions presented here for benefit of the reader. By Linnik's ...
Hhhhhhhhhhh's user avatar
  • 1,042
5 votes
1 answer
392 views

Divergence of primes dividing polynomials

Let $Q : \mathbb{Z} \rightarrow \mathbb{Z}$ be a polynomial. Form the set $$M_{Q} := \{p:\text{ }p\text{ is prime, }\exists n_{p}\in \mathbb{Z}\text{ so that }p|Q(n_{p})\}$$ Is $$\sum_{s \in M_{Q}}\...
Siddharth Iyer's user avatar
1 vote
0 answers
83 views

Prime powers gap of type $(a,b)$

For $n$ a given positive integer, say $r$ is a Galois radius of $n$ of type $(a,b)$, level $l=ab$ and rank $\rho=a+b$ if $n-r=p^a$ and $n+r=q^b$ with both $p$ and $q$ prime. Denote by $PPG_{a,b}(m)$ ...
Sylvain JULIEN's user avatar
2 votes
1 answer
159 views

Is the density of integers $n$ such that the finite sequence $(\omega(n-r)\omega(n+r))_{0\leq r\leq n-1}$ is surjective positive?

Let $\omega(m)$ be the number of prime factors of $m$ regardless of multiplicity. I'm interested in the behavior of the finite sequence $(\omega(n-r)\omega(n+r))_{0\leq r\leq n-1}$ for a given integer ...
Sylvain JULIEN's user avatar
2 votes
1 answer
545 views

Is there a Cramer's conjecture for Sophie Germain primes?

A prime $q$ such that $2q+1$ is also a prime is a Sophie Germain prime. Cramer's conjecture tells gap between consecutive primes is bound by $O(\log^2p)$. Is there a similar conjecture for Sophie ...
Turbo's user avatar
  • 13.9k
9 votes
1 answer
400 views

The difference between consecutive primes in arithmetic progressions

Let $\pi(x)=\sum_{p\leq x}$ denote the prime counting function. A well known result of Baker, Harman, and Pintz on prime gaps states that for $x\geq y\geq x^{0.525}$ we have that $$\pi(x+y)-\pi(x)\gg \...
Eric Naslund's user avatar
  • 11.4k
3 votes
0 answers
158 views

What can be said about the primality of Zsigmondy numbers?

I am cross-posting this from math.stackexchange, as it has received upvotes but no comments/answers after a couple months. Let $\mathcal{Z}(n,a,b)=\frac{\Phi_n(a,b)}{\gcd (\Phi_n(a,b),n)}$ be the $n$-...
Tejas Rao's user avatar
  • 101
5 votes
2 answers
1k views

A question regarding Cramér's proof on prime gaps under the Riemann Hypothesis

Let $p_n$ be the $n$th prime. Assuming the Riemann hypothesis, Harald Cramér proves that $p_n-p_{n-1}\le C(\sqrt p_n \log p_n)$ for sufficiently large $n$. Is there a value known for the constant $C$ ...
EGME's user avatar
  • 1,018
3 votes
0 answers
428 views

Proof of an explicit formula for $\pi_0(x)$

Let $\pi(x)$ denote the prime counting function and $$\pi_0(x) = \lim_{\epsilon \to 0} \frac{\pi(x+\epsilon)+\pi(x-\epsilon)}{2}.$$ I've seen noted in a few references the explicit formula $$\pi_0(x) =...
Jesse Elliott's user avatar
8 votes
2 answers
814 views

Estimates about prime numbers: a lemma in Bourgain's article

For $n\in \mathbb{N}$ with prime decomposition $n=p_1^{r_1}\cdots p_k^{r_k},p_i\neq p_j$, let $A=\{p_1,\cdots,p_k\}$; then the following holds: \begin{equation} |\{q\in \mathbb{N},q<Q: \text{all ...
Dapao Zhang's user avatar
1 vote
0 answers
240 views

Liu's new sieve weight

Does Liu's sieve weight (in his arXiv paper "On the gap between primes") $$sieve(n)=(\sum_{\substack{d_i\mid (n-h_i),i=1,\cdots,k\\ (d_1,\cdots,d_k)\in\mathcal{D}}}\lambda_{d_1,\cdots,d_k} ...
lovent's user avatar
  • 11
1 vote
0 answers
749 views

Can the prime gap record of Liu be improved further?

Let $d$ be the least positive integer such that there are infinitely many distinct prime pairs $\{p,q\}$ with $|q-p|\le d$. The twin prime conjecture is equivalent to $d=2$. In 2013 Yitang Zhang ...
Zhi-Wei Sun's user avatar
  • 15.6k
2 votes
0 answers
144 views

A conjecture about prime test

Conjecture If $\varphi(m)<\varphi(n)$ for all $m<n$,then $n$ is a prime number. I tried to find a counterexample when $n=pq$ ($p,q$ are prime), then we have to find a prime between $(p-1)(q-1)$ ...
ReinhardtΩ's user avatar
4 votes
1 answer
219 views

Numbers $n$ whose representation as the product of two divisors require more digits than that of $n$

Note: Posting in MO since it was unanswered in MSE Let $f(x)$ be the number of digits in the decimal representation of $x$ e.g. $, f(0) = 1, f(1729) = 4$. If $n = ab$ then we can show that $f(ab) > ...
Nilotpal Kanti Sinha's user avatar
4 votes
0 answers
210 views

No perfect patterns in the primes

The primes are equidistributed in the residue classes $1(\!\!\!\mod{4})$ and $3(\!\!\!\mod 4)$. We also know (for example, by Rubinstein-Sarnak) that the patterns cannot be eventually alternating, i.e....
Dr. Pi's user avatar
  • 3,062
9 votes
3 answers
584 views

Why is there an unexpected increase in the density of certain types of Goldbach primes?

Note: Posted in MO since it was unanswered in MSE. I was checking how quickly we can verify Goldbach's conjecture for a given even number $n$ and it was clear that searching backward starting from the ...
Nilotpal Kanti Sinha's user avatar
7 votes
0 answers
335 views

Residues of consecutive primes modulo a fixed integer

It is well-known that the primes are uniformly distributed in residue classes modulo any fixed integer. More precisely, for each integer $q$ and each residue $a \in \mathbb{Z}/q\mathbb{Z}$ that is ...
Jakub Konieczny's user avatar
4 votes
1 answer
235 views

Relation between $\pi$, area and the sides of Pythagorean triangles whose hypotenuse is a prime number

Consider all Pythagorean triangles $a^2 + b^2 = p^2$ in which the hypotenuse $p$ is a prime number. Let $h(x) = \sum_{p \le x}p^2$, $a(x) = \sum_{p \le x}ab$ and $r(x) = \sum_{p \le x}(a+b)^2$. Is it ...
Nilotpal Kanti Sinha's user avatar
1 vote
0 answers
84 views

How common are semiprimes with equally bitsized factors among semiprimes with equal bitsize?

I am curious about the following after having looked at the paper "Almost primes in almost all short intervals", theorem 3 says: Almost all intervals $[x, x + \log^{3.51}{(x)}]$ with $x ≤ X$...
factorn's user avatar
  • 11
5 votes
1 answer
214 views

Remainder terms of congruence sums in sets of positive density

Let $\mathcal{A} \subset \mathbb{N}$ be an infinite sequence with positive density, in the sense that $$ \tag{1} \lim_{x\to\infty} \frac{|\mathcal{A} \cap x|}{x} = c > 0, $$ and define the ...
Joshua Stucky's user avatar
1 vote
1 answer
306 views

Expected number of primes of particular size and from a linear form

Given two distinct primes $P_1$ and $P_2$ picked randomly and uniformly in the interval $[T^2,2T^2]$ consider the set $\chi(P_1,P_2)$ of numbers of form $$xP_1-yP_2$$ where $x,y$ are in $[0,T^{1+\...
Turbo's user avatar
  • 13.9k
9 votes
2 answers
547 views

Primes between $x$ and $x+x^\theta$

Iwaniec [1] proved that $$ \pi(x+x^\theta)-\pi(x) < \frac{(2+\varepsilon)x^\theta}{\eta(\theta)\log x},\ x>x_0(\varepsilon,\theta). $$ with $$ \eta(\theta)=\frac{15\theta-2}{9}. $$ (Actually, he ...
Charles's user avatar
  • 9,114
10 votes
0 answers
350 views

Are there are any attempts utilising sieve theory to attack the general $a p \pm 1$ problem?

It is currently an open question if there are infinitely many primes $p$ such that $2p + 1$ is prime (Sophie Germain primes) or that at least one of $24p \pm 1$ is prime. Could Zhang's method, or the ...
KStar's user avatar
  • 533
3 votes
0 answers
292 views

A prime generating algorithm

I posted this question in MSE around a month ago, but didn't receive any suitable answers. So, I decided to give it a try here as well- I was trying to explain the famous proof of infinitude of primes ...
Sayan Dutta's user avatar
1 vote
1 answer
124 views

why is $R := \mathbb{Z}p +XF[[X]]$ an almost valuation domain?

Recall that an integral domain $R$ with quotient field $K$ is an almost valuation domain if for every $0 \not= x \in K$, there is a positive integer $n$ (depending on $x$) such that $x^n \in R$ or $x^{...
Antony's user avatar
  • 147
0 votes
1 answer
97 views

$l$-th power radioprimal conjecture

I would like to know if some widely believed conjecture, be it GRH, Hardy-Littlewood conjecture, or any other would imply the following statement for some $l>1$: $l$-th power radioprimal growth ...
Sylvain JULIEN's user avatar
10 votes
2 answers
282 views

Non-trivial upper bound for a sum related to $p^{-1}z \pmod q$ and $q^{-1}z \pmod p$

Let $p, q$ be two distinct prime number. I'm trying to provide a non-trivial upper bound for the sum $$S(p, q) = \sum_{1 \leq x < p} \sum_{1 \leq y < q} \frac{1}{\|x / p\| \, \|y / q\| \, \|x/p +...
Seee's user avatar
  • 65
0 votes
0 answers
177 views

Is there a link between Elliott-Halberstam and weak Hardy-Littlewood-Goldbach conjectures?

Let $\theta$ be such that $EH(\theta)$ holds, where $EH$ stands for Elliott-Halberstam. Can one get an explicit lower bound $\delta_{\theta}$ for the quantity $\delta$ appearing in the weak Hardy-...
Sylvain JULIEN's user avatar
3 votes
2 answers
465 views

Least number coprime to a given integer

For a positive integer $n$ let $$f(n):=\min\{m\in \mathbb N: m>1, \gcd(m,n)=1\} .$$ Equivalently, $f(n) $ is the smallest prime not dividing $n$. Is there any upper bound literature for this? It is ...
Dr. Pi's user avatar
  • 3,062
1 vote
0 answers
293 views

Can a lower bound for this weakening of Goldbach's conjecture be reached?

Say a non negative integer $r$ is a primality radius of $n$ if both $n-r$ and $n+r$ are prime, and that a non negative integer $w$ is a Galois radius of $m$ if $\omega(m-w)=\omega(m+w)=1$, where $\...
Sylvain JULIEN's user avatar
13 votes
2 answers
1k views

What is known about the prime number theorem for Beurling generalised primes

Background: Beurling's systems of numbers Beurling considered a sequence of reals $1<x_1<x_2<\cdots <$ as "primes" and then the ordered sequence of all products of these "...
Gil Kalai's user avatar
  • 24.7k
3 votes
0 answers
232 views

Numbers made up of primes from a given set

Take a set $\mathcal P$ of primes and denote by $\langle \mathcal P\rangle $ the set of all natural numbers composed of primes from $\mathcal P$. If \[ \sum _{p\in \mathcal P}\frac {1}{p}\] converges ...
tomos's user avatar
  • 1,381
3 votes
0 answers
117 views

On the Carmichael Lambda function

Let Carmichael function be denoted by $\lambda(n)$. Consider the set $I_m=\{n:\lambda(n)=m\}$. What is known about the cardinality of $I_m$? Let $P_m=\{p\in Primes: p|\ell \mbox{ for some }\ell\in ...
Turbo's user avatar
  • 13.9k
0 votes
0 answers
102 views

On simple examples of unimodularity

$w=z=x+ 1 =y−1$ provides $wz−xy=w^2−(w−1)(w+ 1) = 1$. Hence if $x,y$ are odd then $w,z$ are even and all four integers are close. Is there elementary example where only $w$ is even and all four ...
Turbo's user avatar
  • 13.9k
4 votes
1 answer
400 views

Bounding integrals involving $\operatorname{li}(x)-\pi(x)$

Let $x >0$. How can one find good $O$ bounds on the integrals $$\int_0^x\frac{\operatorname{li}(t)-\pi(t)}{t}dt$$ and $$\int_x^\infty\frac{\operatorname{li}(t)-\pi(t)}{t^2}dt$$ where $\pi(x)$ is ...
Jesse Elliott's user avatar
2 votes
1 answer
461 views

How essential is the vanishing of the Dirichlet $L$-functions to Dirichlet's theorem on primes in arithmetic progressions?

I seem to recall that the prime number theorem (PNT) is equivalent to the fact that the Riemann zeta function $\zeta(s)$ is non-zero on all of $\text{Re}(s) = 1$ (see https://math.stackexchange.com/...
D.R.'s user avatar
  • 831
5 votes
0 answers
326 views

Counting primes, twin primes, cousin primes: unusual approach, connection to some conjectures

I am investigating the following sieve-like algorithm. Let $S_N=\{1,\dots,N\}$. For all primes $p$ with $p_0\leq p \leq M$, we remove from $S_N$ the following elements: all numbers $n\in S_N$ such ...
Vincent Granville's user avatar

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