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18 votes
3 answers
918 views

Can Gauss sums derandomize any heuristic arguments?

I've always been fascinated by the fact that the classical Gauss sum has absolute value $\sqrt p$, which is exactly what we would expect if we were to interpret the Gauss sum as a random walk. In ...
Timothy Chow's user avatar
  • 82.7k
14 votes
6 answers
2k views

Density of numbers having large prime divisors (formalizing heuristic probability argument)

I want to prove that the set of natural numbers n having a prime divisor greater than $\sqrt{n}$ is positive. I have a heuristic argument that this density should be $\log 2$, which is approximately ...
Vipul Naik's user avatar
  • 7,320
14 votes
1 answer
1k views

Normal numbers, Liouville function, and the Riemann Hypothesis

This is a question about whether or not some number $\lambda^*$ is normal in base 2. More specifically, I am wondering if $\lambda^*$ is not normal. Proving it is normal would be next to impossible, ...
Vincent Granville's user avatar
13 votes
4 answers
1k views

What results would follow from or imply "randomness" of the primes?

This question on random versions of deterministic problems reminded me that many conditional results in number theory hold if the primes are in some sense random, and it is common knowledge that the ...
9 votes
6 answers
3k views

Primes are pseudorandom?

I've been reading the wonderful slides by Terry Tao and thought about this question. Primes appear to be quite random, and the formal statement should be that there are some characteristics of primes ...
Ilya Nikokoshev's user avatar
9 votes
2 answers
1k views

Random pseudoprimes vs. primes

(Edit. What I called "pseudoprimes" are known as "Cramér random primes" in the literature, of which I was unaware.) Say that a set $S$ of natural numbers is a set of pseudoprimes if they are (a) ...
Joseph O'Rourke's user avatar
7 votes
0 answers
267 views

Can primes be (almost) random sequence in von Mises sense?

Random models for primes (such as Cramer's model) have been extensively used for informal justification of various conjectures involving primes. It is crucial to understand in what sense sequence of ...
Bogdan Grechuk's user avatar
6 votes
4 answers
2k views

Probability that randomly chosen integers from a restricted set of natural numbers are coprime

We know that the probability $P(k)$ of $k$ randomly chosen integers $(k \ge 2)$ from the set of natural number are coprime is $$ P(k) = \frac{1}{\zeta(k)}. $$ I am looking at a special case of ...
Nilotpal Kanti Sinha's user avatar
6 votes
1 answer
481 views

Probabilistic Proofs of Key Number-Theoretic Results

Given a positive integer $n$, let $p$ be the largest prime less than or equal to $n$. Let $N(n)=2^{C_2}\cdots p^{C_p}$ be uniformly distributed from $1$ to $n$, and $M(n)=2^{Z_2}\cdots p^{Z_p}$ where ...
The Substitute's user avatar
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
4 votes
0 answers
536 views

Is the integer factorization into prime numbers normally distributed?

Edit: Sorry, for the inconvenience: I have edited the question, since there was a misconception in my thinking. Let $P_1(n) := 1$ if $n=1$ and $\max_{q\mid n, \text{ } q\text{ prime}} q$ otherwise, ...
mathoverflowUser's user avatar
3 votes
1 answer
401 views

Probability of finding a prime number between $x-\ln(x)$ and $x+\ln(x)$

Using my computer, I found that in the interval $[1, N]$ the probability of finding a prime number between $x-\ln(x)$ and $x+\ln(x)$ is greater than constant $c$ where $N=10^2, 10^3,...,10^{9}$, $x$ ...
Đào Thanh Oai's user avatar
3 votes
2 answers
462 views

using distribution of primes to generate random bits?

In his popular science book The Music of the Primes, Marcus du Sautoy tries to link the truth of the Riemann Hypothesis to the "randomness" of the primes. To do this, he invokes the idea of a "fair ...
user19727's user avatar
  • 371
3 votes
0 answers
286 views

What is the value of this simple game with primes?

Consider the following game. Alice selects an integer $n$ from $[1,b]$, while Bob selects an integer $m$ from $(a,b]$ (for concreteness, you may choose $a=10^{10}$ and $b=10^{1000}$). Alice wins if $m-...
Bogdan's user avatar
  • 781
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
0 answers
98 views

Primes as expected values?

This is a follow-up question, which is related to the answer of this quesiton: Is there a connection of prime numbers and extreme value theory? I will duplicate the answer here, so this question is ...
mathoverflowUser's user avatar
2 votes
0 answers
87 views

The covariance of certain random variable

We define two random variables $X_n,Y_n $ on the sample space $\{1,2,3,\cdots,n\}$ with counting measure. We denote by $C_n$ the covariance of theses two random variables: $C_n=Cov(X_n,Y_n)$. ...
Ali Taghavi's user avatar
1 vote
2 answers
513 views

Primes as uncorrelated random variables [closed]

The heuristic justification section of the Wikipedia article about Goldbach's conjecture says that the argument that suggests that the number of twin primes below $x$ should be roughly $\dfrac{x}{\...
Sylvain JULIEN's user avatar
1 vote
1 answer
390 views

Probability that p and q are both prime provided q-p=2r

Hello, I would like to know whether there is a way, thanks to the prime number theorem, to give some kind of an equivalent of the probability that two positive integers $p$ and $q$ less than a given ...
Sylvain JULIEN's user avatar
1 vote
1 answer
199 views

Asymptotic for the probability that a number has $k$ prime factors less than $Q$

If we let $\omega_Q(n)$ denote the number of distinct prime factors of $n$ less than a bound $Q$, then what asymptotic formulas exist for $\Pr_{n\in\mathbb{N}}[\omega_Q(n)=k]$ as $Q\to\infty$ if $k$ ...
Milo Moses's user avatar
  • 2,902
1 vote
0 answers
641 views

Some stuff related to the twin prime conjecture

I am making three statements here, and my question is about statement 2, asking if someone can prove or disprove it. A (possibly weaker) version of statement 2 was proved as an answer to a former ...
Vincent Granville's user avatar
0 votes
0 answers
102 views

Formalizing the "pseudorandomness" of primes

Many conjectures about primes seem to revolve around the idea of "primes are random". So I thought about how this "randomness" may be formally defined, and came up with the ...
XM73's user avatar
  • 1
0 votes
0 answers
257 views

Unexpected autocorrelations in sequence of primes modulo 4

It is well known that there is a little bias in the distribution of prime residues modulo 4. But the bias eventually vanishes. I looked at the first million primes, and the counts are as follows: ...
Vincent Granville's user avatar