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2 votes
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Error bounds for $\pi(x)-Li(x)$ and convergence of the associated Dirichlet integral

Following On the integral $I_s =\int_{1}^{\infty} (\pi(x)-Li(x))x^{-s-1} dx$, define $$I_{s}=\int_{1}^{\infty} (\pi(x)-Li(x))x^{-s-1} \mathrm{d}x,$$ where $\pi$ denotes the prime counting function ...
Q_p's user avatar
  • 1,019
2 votes
0 answers
99 views

A problem in modular roots

We have three mutually coprime integers $r,t,M$ where $M\asymp K^{\frac12-2\epsilon}$ and $r,t\asymp K^{\frac14+\epsilon}$ holds with some fixed $\epsilon>0$ and $K>0$ is a large parameter. ...
Turbo's user avatar
  • 13.9k
2 votes
0 answers
158 views

On the connection between $\pi(x)-Li(x)$ and $\theta(x)-x$

Let $\pi(x)$ be the number of primes $p$ not exceeding $x, \theta(x) = \sum_{p\leq x} \log p$ and $Li(x)$ be the logarithmic integral. Is it true that $$\pi(x)-Li(x) = \theta(x) - x + O(x^{1/2}\log^{...
Q_p's user avatar
  • 1,019
2 votes
0 answers
167 views

What about series involving strong primes?

I know about the importance in analytic number theory of the sutdy of series involving prime numbers or constellations of prime numbers, for example, if I am not wrong, major theorems are Mertens' ...
user142929's user avatar
2 votes
0 answers
112 views

Queries on distribution of prime divisors by magnitude?

Erdos-Kac law state a typical number of magnitude $n$ has $\log\log n$ prime factors and we know probability of square free integers is $\frac{6}{\pi^2}$. What is the probability distribution of ...
Turbo's user avatar
  • 13.9k
2 votes
0 answers
121 views

How to choose a prime p s.t. n-th cyclotomic polynomial splits into as much as possible irreducible polynomials while p is almost constant size?

The reason I ask this question is that cyclotomic polynomial is critical to the construction of lattice-based cryptography. In most of the existing lattice-based cryptographic schemes, $n$ is usually ...
user67451's user avatar
2 votes
0 answers
76 views

Is there an estimate available for a sum of the form $\sum_{\mathbf{x} \equiv \mathbf{a} (H) } \mu^2(x_1 x_2)$

I am interested in a sum of the shape $$ \sum_{ \substack{ 1 \leq x_1, x_2 \leq B\\ \mathbf{x} \equiv \mathbf{a} (H) } } \mu^2(x_1 x_2). $$ I figured it must have been considered before, but I have ...
Johnny T.'s user avatar
  • 3,625
2 votes
0 answers
147 views

Skewes' number and the ratio $\frac{\operatorname{li}(x^{1/2})}{\operatorname{li}(x)-\pi(x)}$

(A complementary post is here.) Given the prime counting function $\pi(x)$ and the logarithmic integral $\operatorname{li}(x)$, we have Table 1, $$\begin{array}{|c|l|} \hline x&\operatorname{li}...
Tito Piezas III's user avatar
2 votes
0 answers
107 views

Maximization of product over primes

I have the following maximization problem. Let $f(p)$ be a real function on the primes, having values in $(0,1)$. Assume that $Y$ is a given (large) positive number, and that we have the bound $$\...
Kurisuto Asutora's user avatar
2 votes
0 answers
149 views

$f(x)$-th largest number of prime factors

Given a sufficiently well-behaved function $1\le f(x)\le x$ and a multiset $S=\{\omega(n): 1\le n\le x\}$, what can be said about the asymptotics of the $f(x)$-th largest member of $S$? In other words,...
Charles's user avatar
  • 9,114
2 votes
0 answers
392 views

How big can a set of integers be if all pairs have bounded gcd

In this recent MO question, it was shown that the maximal cardinality of a subset $A(M,N)$ of $[1,N]$ where the pairwise GCD's of all set elements are upper bounded by $M,$ with $M^2\leq N$ has size ...
kodlu's user avatar
  • 10.4k
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
2 votes
0 answers
388 views

Relation between Maier's theorem and a conjecture of Montgomery and Soundararajan

Let us consider the number of primes in the interval $[N,N+h]$, with $h\leq N$. According to the answer given by Lucia to a previous question on the distribution of primes, it is natural to consider ...
user45947's user avatar
  • 965
2 votes
0 answers
292 views

Prime divisors of the difference set

Fix $c\in(0,1)$, and let $N$ be a (large) positive integer. Given a set $A=\{0=a_1<\dots<a_n=N\}$ of density $\alpha:=n/N>c$ with $\gcd(A)=1$, I want to find a prime dividing as few ...
Seva's user avatar
  • 23k
2 votes
0 answers
318 views

Pierpont primes

A Pierpont prime is a prime $p$ that can be written as $$p=2^u 3^v + 1.$$ What is known about Pierpont primes? I'm not a number theorist, and the best I can find is http://en.wikipedia.org/wiki/...
Thomas S's user avatar
2 votes
2 answers
338 views

Weak form of Brocard's conjecture

I ask this out of curiosity, motivated by a question asked by one of my students. The Brocard's conjecture claims that there exist at least four prime numbers between $p_{i}^2$ and $p_{i+1}^2$, where ...
Francesco Polizzi's user avatar
1 vote
3 answers
845 views

How do estimates on $N_\chi(\alpha,T)$ lead to the Dirichlet prime number theorem for arithmetic sequences?

Let $ N_\chi(\alpha,T)$ be the number of zeros of $L(s=\sigma+it,\chi) = \sum \frac{\chi(n)}{n^s}$ where $c > 0$ and $(\sigma,t) $ are in the rectangle $ [\alpha,1] \times [-T,T]$. In various ...
john mangual's user avatar
  • 22.8k
1 vote
1 answer
317 views

An explicit value for a bound proof

I saw a proof that $|p_n - li^{-1}(n)| \leq n e^{-c \sqrt{\ln(n)}} $, without saying anything about $c$ ! My questions is, what the explicit value of $c$ ?? It just says for some number $c$ without ...
user avatar
1 vote
1 answer
172 views

Are all integers up to $x$ but possibly $O_{\varepsilon}(x^{\varepsilon})$ the sum of $a$ squares and $b$ primes with $a+b\leq 3$?

This question is related to https://math.stackexchange.com/questions/3710032/conjecture-all-but-21-non-square-integers-are-the-sum-of-a-square-and-a-prime. We know since Lagrange that every natural ...
Sylvain JULIEN's user avatar
1 vote
2 answers
182 views

Prime factors bounded by $k$

Let $S$ be the set of integers with largest prime factor bounded by a given positive integer $k$. Is there a formula for the asymptotic density of such a set $S$?
pallab1234's user avatar
1 vote
2 answers
326 views

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
1 vote
1 answer
867 views

$n$th prime: a better approximation

Let $p_n$ be the $n$-th prime, then from Wikipedia I got that $p_n \approx n \left(\ln n + \ln \ln n -1 + \frac{\ln \ln n-2}{\ln n}+\frac{6\ln \ln n-( \ln \ln n)^2-11}{\ln^2 n} \right)$. What is a ...
user avatar
1 vote
1 answer
314 views

Inequality of three prime factors of $x^2-1$

This is about my experimental math observation on prime factorization of $x^2-1$ We can see, for many $x\in \mathbb{Z}_+$, the expression $x^2-1=(x-1)(x+1)$ gives result as a product of twin prime. ...
Pruthviraj's user avatar
1 vote
1 answer
550 views

Proof that $p_{n+1}-p_n\gg\frac{\log \log \log p_n}{\log \log \log \log p_n} \log {p_n}$ [closed]

I cannot find a proof of this theorem. May anyone assist? $p_{n+1}-p_n\gg\frac{\log \log \log p_n}{\log \log \log \log p_n} \log{p_n}$
Cameron Barbeau's user avatar
1 vote
3 answers
378 views

Is this product, involving consecutive primes, always less than or equal to $1$?

i don't know how to write math in Latex so i will try to explain it simply, if we multiply $$\frac{p(i)^2}{p(i)^2-1}\prod_{j=1}^5\frac{p(i+j)^2-1}{p(i+j)^2} ,$$ where $p(i)$ denote the $i$-th ...
user avatar
1 vote
4 answers
1k views

Distribution of composite numbers

I have moved this question to math.stackexchange.com. People who are interested in this question can discuss at :https://math.stackexchange.com/questions/1272431/distribution-of-composite-numbers ...
Xuexing Lu's user avatar
1 vote
1 answer
343 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
1 answer
130 views

Prime inequality $P_{n.m}$ $<$ $P^{m}_n$ [closed]

Let $P_n$ be nth prime, where $n,m \in$ $\mathbb{N}$, $n,m >1$. How i can show that $P_{n.m}$ $<$ $P^{m}_n$. I tried to used $PNT$ but that feels like overkill, is this inequality already ...
One Above All's user avatar
1 vote
2 answers
233 views

Inquiry on the Chebyshev $\theta$ function

Let $$\theta(x)=\sum_{p\leq x} \log p$$ be the Chebyshev function over primes $p$. Computational evidence seems to suggest that $\theta(x) < x$ for every sufficiently large $x$. But is it true ?...
UserABC's user avatar
  • 13
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
1 vote
1 answer
385 views

Convergence of a double sum involving prime numbers

This has been moved from math.stackexchange; I am attempting to prove/disprove convergence of the following sum $$ \lim_{n \to \infty} \frac{1}{n} \sum_{p \leq n} \sum_{k=0}^\infty \ln p \left\{\frac{...
Brian's user avatar
  • 1,549
1 vote
1 answer
601 views

reference on Dirichlet theorem on primes in arithmetic progression

I appreciate if you could help me to find a reference (and a proof). Combining Dirichlet theorem on primes in arithmetic progression with Chebotarev densitiy theorem, we know that given two positive ...
Pablo Spiga's user avatar
1 vote
1 answer
374 views

$\{ x/p\} $ on average

This is a vague question: Lemma 2.2 of Friedlander and Lagarias' "On the distribution in short intervals of integers having no large prime factor" says that $$\sum _{p\leq w}\left (\{ x/p\} -...
tomos's user avatar
  • 1,381
1 vote
1 answer
365 views

Equation of the Chebyshev $\psi$ function

Consider $\Psi(x)$ to be the Chebyshev function given by $$\Psi(x)=\sum_{n\leq x} \Lambda(n)$$ where $\Lambda(n)$ is the Mangoldt function which is equal 0 unless $n $ is prime power, and let $(E)$ ...
Aster Phoenix's user avatar
1 vote
1 answer
153 views

Specializing non-trivial primality tests

Primes $p$ are integers with no factors (composite allowed) in $[1,p]$. There is a polynomial time test for them. Given an interval $[a,b]$ what is the best way to test given integer $q$ has no ...
Turbo's user avatar
  • 13.9k
1 vote
1 answer
729 views

Could the complex zeros of Riemann zeta function be of the form $ s=0.5+ik$ with $k$ a positive integer? [closed]

I have checked in Andrew Odlyzko, Tables of zeros of the Riemann zeta function, to know if there is an example of zeros of Riemann zeta function with integer imaginary parts, but I don't see that. I ...
zeraoulia rafik's user avatar
1 vote
1 answer
231 views

An estimation of $p_n$

There seems to exist an asymptotic line $$\displaystyle a+bx\sim \frac{x e^x}{p_{n}-x e^x}\; ,\;n=\lfloor e^x\rfloor\tag1$$ Which suggests an estimation $$\displaystyle g(n)=\Big(1+\frac{1}{a+b\ln ...
Lehs's user avatar
  • 862
1 vote
1 answer
199 views

Weights in the proof of Chen's theorem in Nathanson's "Additive Number Theory The Classical Bases"

I was reading Professor Nathanson's graduate texts in mathematics 164: "Additive Number Theory The Classical Bases" (http://www.alefenu.com/libri/nathansonbases.pdf), and I was wondering if ...
Rick's user avatar
  • 13
1 vote
1 answer
131 views

Consecutive non-powerful integers

Pair of sequences $\ v_n\ $ and $\ U_n\ $ of integers start as in the following table: [\begin{array}{rrrrrrrrrr} n= & 0 & 1 & 2 & 3 & 4 & 5 & 6 & 7 & \ldots \\ ...
Wlod AA's user avatar
  • 4,786
1 vote
1 answer
203 views

Best bound on $p, p+2k$ with $k$ fixed

Given some integer $k>0$, there are $O(x/\log^2 x)$ primes $p \le x$ such that $p+2k$ is also prime. It has been conjectured at least since Hardy-Littlewood that $$ \pi_{2k}(x) \sim c_{2k}\int_2^x\...
Charles's user avatar
  • 9,114
1 vote
1 answer
271 views

Least simultaneous quadratic non-residue

Suppose $p,q$ are distinct primes with least quadratic non-residues $n_p$ and $n_q$ respectively. Can one bound the least $n$ for which $\left(\frac{n}{p}\right)=\left(\frac{n}{q}\right)=-1$ in terms ...
Brando's user avatar
  • 671
1 vote
1 answer
204 views

Behavior of a quantity related to Fermat's 4n + 1 Theorem

One of Fermat's theorems states that if $p = 4n + 1$ for some integer $n$, then $p$ can be expressed uniquely as a sum of two squares, $p = a^2 + b^2$. I am working on a problem and I would like to ...
Mustafa Said's user avatar
  • 3,699
1 vote
2 answers
955 views

Numbers of a different order?

Let $d_r$ be a divergent series of positive terms and let $s_r = \sum_{i=1}^{r}d_r$. We are interested in the sequence of numbers $S_{d_r} = s_1, s_2, \ldots$. For example if $d_r = 1/r$ the $s_r = ...
user20174's user avatar
  • 459
1 vote
2 answers
383 views

Is there any way to estimate this functions: $f(n)=\sum_{d|n}d\varphi(d)$ and $g(n)=\sum_{d|n}\frac{\varphi(d)}{d}$?

Let that $n$ be a natural number and $\varphi(n)$ be the Euler totient function. Is there any formula or estimation for computing functions $f,g$ such that: $$ f(n)=\sum_{d\mid n}d\varphi(d) $$ and $$ ...
Jamal Farokhi's user avatar
1 vote
1 answer
286 views

GRH and the Euler product

Let $L(\chi, s)$ be the Dirichlet L-Function of a primitive character $\chi$. I believe, if I’m not mistaken, the convergence of the Euler product of $L(\chi, s)$ in the critical strip is known to be ...
edward cornfoot'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
1 vote
1 answer
153 views

Is $P_{2n} \ge 2P_n$ and $\pi(2x) \le 2\pi(x)$ inconsistent to the Prime k-tuple conjecture?

I posed a conjecture as follows that is a special case of Second Hardy–Littlewood conjecture: For $n, x \ge 2$ be two integers then: $$P_{2n} \ge 2P_n$$ and $$\pi(2x) \le 2\pi(x)...
Đào Thanh Oai's user avatar
1 vote
1 answer
466 views

Proof of prime gap bound? [closed]

In another question on mathoverflow (What is the best currently proven bounds on prime gaps?) the following bound on the prime gap was quoted: $G(X)\ll \frac{X^{0.525}}{\log X}$ How do you prove this, ...
GenRincewind's user avatar
1 vote
1 answer
175 views

Sequence of consecutive gaps in prime numbers

Let $p_i$ be $i^{th}$ prime number (for example $p_4=7$). Is there $m=m(n, k)$ such that $n \leq \min \{p_{m+i}-p_{m+i-1} : 1 \leq i \leq k\}$ for every $n$ and $k$? Even, consider the problem for $k=...
Arash Ahadi's user avatar
1 vote
1 answer
177 views

Arithmetic progressions, given a prime

I have recently become interested in reading a little more on certain directions regarding primes in arithmetic progressions (AP). I would appreciate specific paper references (with the journal and ...
user avatar