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Goldbach conjecture reformulation [closed]

As thought, the question below is a reformulation of the goldbach conjecture. $ S = \{K - ap \mid a \geq 3, p \text{ is prime} < K/2 \} $, where $ a $ is an odd integer greater than or equal to 3, ...
Felix Fowler's user avatar
4 votes
1 answer
251 views

Density of semiprimes in arithmetic progression

Let $n,a,b$ be integers such that $n$ and $a$ are coprime, and $n$ and $b$ are also coprime. According to the Prime number theorem for arithmetic progressions, the primes which are $a\mod n$ have the ...
Riemann's user avatar
  • 654
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
323 views

Primes in arithmetic progressions: weak version of Linnik's theorem with prime power modulus?

Looking at a problem in representation theory I ran into a question on small primes in arithmetic progressions. Let me begin with a short summary of results on small primes in arithmetic progressions. ...
Steffen Kionke's user avatar
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
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
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
4 votes
1 answer
215 views

Primes in arithmetic progressions above a given threshold

Given co-prime $a,b$, Dirichlet's theorem states that there are infinitely many primes in the arithmetic progression $M = \{ a + bn : n \in \mathbb N\}$. Linnik's theorem asserts that the first such ...
Christoph Haase's user avatar
3 votes
2 answers
417 views

Infinitely many primes in particular progressions

I'm faced with the following problem on primes. Does someone have any clue? Is it (a reformulation of) an open problem? Let $d$ be a positive integer, $d\geq 2$. By Dirichlet's theorem, there is an ...
E. Delaygue's user avatar
5 votes
1 answer
416 views

Does every prime $p$ appear in a $p$-term arithmetic progression of primes? [duplicate]

This is a follow-up to an earlier question. The answer to that question was found on this page. The discussion on OEIS seems to suggest that, for any prime $p$, there should exist a $p$-length ...
Kim's user avatar
  • 4,164
29 votes
4 answers
3k views

Is there an 11-term arithmetic progression of primes beginning with 11?

i.e. does there exist an integer $C > 0$ such that $11, 11 + C, ..., 11 + 10C$ are all prime?
Kim's user avatar
  • 4,164
26 votes
1 answer
1k views

What is the status on this conjecture on arithmetic progressions of primes?

The Green-Tao theorem states that for every $n$, there is an arithmetic sequence of length $n$ consisting of primes. For primes, $p$, let $P(p)$ be the maximum length of an arithmetic progression of ...
Gorka's user avatar
  • 1,835
2 votes
2 answers
395 views

About consecutive integers covered by arithmetic progressions

Help me please to solve the following problem. There are $n$ arithmetic progressions of the form: $$(2i+1)k + x_i,~~~~ i = 1,\ldots,n, k \geq 0$$ Initial integer terms $x_i \geq 0$ are varying. ...
Dmitry Pyatin's user avatar
3 votes
1 answer
359 views

Primes in simultaneous arithmetic progressions

Suppose we're given four positive integers $a$, $b$, $c$, $d$ such that $a$ and $b$ are coprime, and $c$ and $d$ are coprime. Is there a non-negative integer $k$ such that both $ak+b$ and $ck+d$ are ...
Filip Nikšić's user avatar
9 votes
1 answer
843 views

Bounded gaps between primes in arithmetic progressions

Has Zhang's work on bounded gaps between primes been extended to the following theorem? For any arithmetic progression $an+b,\gcd(a,b)=1$, there is a constant $H$ (depending only on $a$) such that ...
Wojowu's user avatar
  • 28.2k
11 votes
2 answers
1k views

Most dense subset of numbers that avoids arbitrarily long arithmetic progressions

The famous Green-Tao theorem says that there exist arbitrarily long sequences of primes in arithmetic progression. I am wondering: How dense can a subset $S \subset \mathbb{N}$ be and still avoid ...
Joseph O'Rourke's user avatar
4 votes
1 answer
980 views

Smallest prime in an arithmetic progression

Let $\{a_n\}_{n\in\mathbb{N}}$ be defined as $a_n = a + bn$ for some $a, b >0,(a, b) = 1$. Are there good bounds on the minimal $k$ s.t. $a_k$ is prime. It is well known that there are infinitely ...
Mayank Pandey's user avatar
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
5 votes
2 answers
643 views

Primes from a Dirichlet sequence and an irrational number

From Dirichlet's theorem on arithmetic progressions, if $\text{gcd}(a,b)=1$ we know $\{ak+b\}_{k\ge 0}$ contains infinitely many primes. Let those primes be $p_1,p_2,\cdots$. Then the real $$\alpha=0....
shadow10's user avatar
  • 1,090
10 votes
4 answers
2k views

Arbitrarily long arithmetic progressions

Are there arbitrarily long arithmetic progressions in which all the prime factors of all the terms are at most $N$, for some $N$? Assume all the terms are positive and the sequence of terms is ...
shadow10's user avatar
  • 1,090
0 votes
0 answers
239 views

Conjecture about distribution of primes in arithmetic progression

For my work, i need the following Conjecture: Let $N$ large number such that exist a prime number $q$ and $A>\frac{1}{2}$ such that $N^{1/2}<N^{A}\leq q-1<N.$ Then $\forall a\in\left[1,\, q\...
user42503's user avatar
9 votes
2 answers
2k views

On the prime number theorem in arithmetic progression

The prime number theorem tells us that , if $\pi\left(x\right)$ denotes the number of primes less than or equal to $x$, we have $$\pi\left(x\right)\sim\frac{x}{\log x}.$$ In a similar manner ...
Marco Cantarini's user avatar
9 votes
2 answers
1k views

Are there five consecutive primes in arithmetic progression?

For example 3 consecutive primes in arithmetic progression 3,5,7 distance 2 151,157,163 distance 6 4 consecutive primes in arithmetic progression ...
Sipendr Sinha's user avatar
14 votes
1 answer
1k views

Small primes in arithmetic sequences

Fix an integer $a>1$. For $n \geq 1$ an integer, let $\pi_{n,1}(an)$ the number of primes $p \leq an$ such that $p \equiv 1 \pmod{n}$, and $\pi(an)$ the number of all primes $p \leq an$. Let $$Q_a(...
Joël's user avatar
  • 26k
8 votes
1 answer
863 views

On the least prime in arithmetic progressions

My question concerns the least prime (denoted $p(a, q)$) in the arithmetic progression $a \pmod q$ where $a$ and $q$ are coprime. Quite a time ago Linnik demonstrated that $$p(a, q) \ll q^L$$ for some ...
kdr's user avatar
  • 463
11 votes
2 answers
3k views

least prime in a arithmetic progression

Hello Here I want to consider the simplest arithmetic progression $n\equiv 1\pmod{q}$ where $q$ is a prime. Is it true that we can find a prime $p\leq q^2$ in this arithmetic progression? This ...
M.B's user avatar
  • 2,508
1 vote
1 answer
214 views

Primes of the form $p_{i_1}p_{i_2}\cdots p_{i_n}+2k$

Let $S_{n,k}$ be the set of all numbers that can be written as the product of $n$ odd primes plus $2k$. Are there integers $n>1$ and $k>1$ such that $S_{n,k}$ contains finite number of primes?
hakuna's user avatar
  • 61
5 votes
2 answers
641 views

Asymptotic Distribution of Primes

Given an integer $n$ and let $1\leq m\leq n$ be such that $n$ and $m$ are coprimes define $$ \mathcal{N_{n,m}}:=\text{the set of primes $p$ such that $p\equiv{m}\hspace{0.1cm}\mathrm{mod}(n)$}. $$ ...
ght's user avatar
  • 3,626
4 votes
5 answers
2k views

residue classes of primes, covering intervals and bounds on the different ways

Take the first $n$ primes $p_1,...,p_n$ and the primorial $P_n$ .Denote by $p_i$ every prime bigger than $p_n$ and smaller than $P_n$. 1) Is that true that there always be a number in any interval of ...
Asterios Gkantzounis's user avatar
8 votes
1 answer
1k views

Are most primes in a prime arithmetic progression of length at least 3?

Following the following two previous questions on mathoverflow: Are all primes in a PAP-3? and Covering the primes by 3-term APs ? I have attempted to show that infinitely many primes are in an ...
Stanley Yao Xiao's user avatar
5 votes
1 answer
310 views

non-asymptotic Bertrand-type theorems for arithmetic progression

It is well known that primes of form $4k+3$, call them $3=q_1 < q_2 < \dots$ satisfy $q_{n+1}/q_n\rightarrow 1$ (and even $q_n=\frac{n}{2\log n}(1+o(1))$). I would be glad to see results of ...
Fedor Petrov's user avatar
2 votes
1 answer
1k views

Covering Systems of infinite sets of residue classes mod primes

Take an infinite set of distinct primes and a (edit: or 2 , etc.) residue class for every prime. For exammple you can take all the primes bigger than some prime or the primes of a specific form (i.e. ...
Asterios Gkantzounis's user avatar
7 votes
1 answer
833 views

Primes in arithmetic progressions

Denote by $\pi(x,a,q)$ the number of primes $p\le x$ of the form $p=qk+a$ and $E(x,a,q)=\phi(q)^{-1}\mathrm{Li}(x)-\pi(x,a,q)$. What is the strongest conjectured bound on $E(x,a,q)$ in terms of $x,q$?
Alex's user avatar
  • 661
22 votes
1 answer
2k views

Are all primes in a PAP-3?

Van der Corput [1] proved that there are infinitely many arithmetic progressions of primes of length 3 (PAP-3). (Green & Tao [2] famously extended this theorem to length $k$.) But taking this in ...
Charles's user avatar
  • 9,114
4 votes
1 answer
3k views

Is there another proof for Dirichlet's theorem? [duplicate]

Possible Duplicate: Is a “non-analytic” proof of Dirichlet’s theorem on primes known or possible? Dirichlet's theorem on primes in arithmetic progression states that there are ...
Hashem sazegar's user avatar
15 votes
1 answer
4k views

The Green-Tao theorem and positive binary quadratic forms

Some time ago I asked a question on consecutive numbers represented integrally by an integral positive binary quadratic form. It has occurred to me that, instead, the Green-Tao theorem may include a ...
Will Jagy's user avatar
  • 25.7k
8 votes
2 answers
576 views

Primes in quasi-arithmetic progressions?

Suppose $\alpha > 1$ is irrational. Are there infinitely many primes of the form $\left\lfloor \alpha n \right\rfloor$? Is the number of $p \leq X$ of this form $\sim \alpha^{-1} X (\log{X})^{-1}$...
David Hansen's user avatar
  • 13.1k
62 votes
1 answer
14k views

Is the Green-Tao theorem true for primes within a given arithmetic progression?

Ben Green and Terrence Tao proved that there are arbitrary length arithmetic progressions among the primes. Now, consider an arithmetic progression with starting term $a$ and common difference $d$. ...
Akela's user avatar
  • 3,699
12 votes
3 answers
929 views

Mertens-like sum in arithmetic progressions

I find myself needing a good estimate for $\sum_{p\le x,\, p\equiv a\bmod q} 1/p$, perhaps something like $$ \sum_{p\le x,\, p\equiv a\bmod q} \frac1p = \frac{\log\log x}{\phi(q)} + b(q,a) + O\big(\...
Greg Martin's user avatar
  • 12.8k
3 votes
1 answer
1k views

Strengthening of Dirichlet's theorem on arithmetic progressions

Hello all, Dirichlet's famous theorem asserts that any arithmetic progression $\lbrace ax+b | x \in {\mathbb N}\rbrace$ contains infinitely many primes if a and b are relatively prime. I am ...
Ewan Delanoy's user avatar
  • 3,595
69 votes
4 answers
14k views

Is a "non-analytic" proof of Dirichlet's theorem on primes known or possible?

It is well-known that one can prove certain special cases of Dirichlet's theorem by exhibiting an integer polynomial $p(x)$ with the properties that the prime divisors of $\{ p(n) | n \in \mathbb{Z} \}...
Qiaochu Yuan's user avatar
8 votes
1 answer
880 views

Upper bound for number of k-term arithmetic progressions in the primes

Normal heuristics give that number of k-term arithmetic progressions in [1,N] should be about $$c_k\frac{N^2}{\log^kN}$$ for some constant $c_k$ dependent on k. The paper of Green and Tao gives a ...
Thomas Bloom's user avatar
  • 7,013
7 votes
2 answers
564 views

Smallest k-term AP of primes

Let $S(k)$ denote the smallest integer such that there exists a k-term arithmetic progression of primes among the integers $[1,S(k)]$. Green and Tao have an unpublished note that gives a very large ...
Mark Lewko's user avatar
12 votes
1 answer
814 views

Covering the primes by 3-term APs ?

Hello, the Green-Tao theorem says infinitely many k-term Arithmetic Progressions exist for any integer k. My question is: can we actually partition the primes into 3-term APs only (or is there a ...
Thomas Sauvaget's user avatar
16 votes
4 answers
2k views

Arithmetic progressions without small primes

The following question came up in the discussion at How small can a group with an n-dimensional irreducible complex representation be? : Is it known that there are infinitely many primes p for which ...
David E Speyer's user avatar