All Questions
Tagged with reference-request nt.number-theory
1,408 questions
6
votes
2
answers
339
views
Sum of divisors and LCM in determinants
$\newcommand{\lcm}{\operatorname{lcm}}$Let $\gcd(i,j)$ and $\lcm(i,j)$ be the greatest common divisor and least common multiple of the pair of positive integers $i$ and $j$. Denote the sum of divisors ...
8
votes
1
answer
355
views
The distribution of certain Galois groups
Let $f(x)$ be a polynomial of degree $d$ with integer coefficients. Let $G_p^+$ be the Galois group of the polynomial $f(x)-y$ over $\overline{\mathbb{F}}_p(y)$ and $G_p$ be the Galois group of the ...
6
votes
2
answers
1k
views
Reference for universal elliptic curves
I've seen the following sentence come up in a few papers:
Consider the modular curve $Y_1(N)$ and let $E$ be the universal elliptic curve over $Y_1(N)$.
This comes up in Deligne's construction of ...
2
votes
0
answers
489
views
On quasi-modular forms with integer Fourier coefficients
It is well-known that the ring $M$ of modular forms has the structure $M=\mathbb{C}[E_4,E_6]$, where $E_k$ are the Eisenstein series.
It is also known that one can define the concept of quasi-modular ...
3
votes
1
answer
280
views
Computing mth power residue symbols
Let's say I have a two odd primes, $p, q$ and $K$ is the field $\mathbb{Q}(\zeta_{pq})$. Let's say $\alpha \in \mathcal{O}$ is an arbitrary element in the ring of integers of $K$, $\frak{b} \subset \...
2
votes
0
answers
156
views
A question on terminology for sequences satisfying $\gcd(a_m,a_n)=a_{\gcd(m,n)}$
How do you refer to those sequences $\{a_{n}\}_{n \in \mathbb{Z}^{+}}$ of integers that satisfy the condition $\text{gcd}(a_{m}, a_{n}) = a_{\text{gcd}(m,n)}$ for every $(m,n) \in \mathbb{Z}^{+} \...
5
votes
0
answers
104
views
Exponential sums with monomials with divisor-function coefficients
In their paper "Exponential Sums with Monomials," Fouvry and Iwaniec study exponential sums roughly of the form
$$
\sum_{m_1 \sim M_1} \cdots \sum_{m_r \sim M_r} c_1(m_1) \cdots c_r(m_r) e\...
17
votes
1
answer
1k
views
Catalan's constant fast convergent series
NOTE. UPDATE 2 introduces proven series for Catalan's constant that is possibly the fastest currently known.
Working with some conjectured continued fractions that were published here, I have found ...
9
votes
1
answer
400
views
The difference between consecutive primes in arithmetic progressions
Let $\pi(x)=\sum_{p\leq x}$ denote the prime counting function. A well known result of Baker, Harman, and Pintz on prime gaps states that for $x\geq y\geq x^{0.525}$ we have that
$$\pi(x+y)-\pi(x)\gg \...
17
votes
2
answers
938
views
Has the following problem, resembling the lonely runner conjecture, been studied?
Given $n$, what is the smallest value $\delta_n$ satisfying the following:
For any group of $n$ runners with constant but distinct speeds,
starting from the same point and running clockwise along the ...
1
vote
0
answers
174
views
Books about number theory and operator algebras
Does anyone know books that covers both operator algebras and number theory. Actually, a number theory books that has operator algebraic approaches.
6
votes
1
answer
546
views
On Cramér's theorem about roots of Zeta function
Cramér proved the following theorem (see the announcement in [1] and [2]):
Consider the following function:
$$V(z)=\sum_k e^{\rho_kz}$$
Where $\rho_k$ runs through non trivial zeta zeros with $Im(\...
11
votes
1
answer
2k
views
Has this number-theoretic constant been studied?
Unless I made a mistake, the expected value of the largest exponent in the prime factorization of random positive integer (defined in the appropriate way) is $$\eta := \sum_{n=1}^\infty \Big(1-\zeta(n)...
3
votes
0
answers
158
views
What can be said about the primality of Zsigmondy numbers?
I am cross-posting this from math.stackexchange, as it has received upvotes but no comments/answers after a couple months.
Let $\mathcal{Z}(n,a,b)=\frac{\Phi_n(a,b)}{\gcd (\Phi_n(a,b),n)}$ be the $n$-...
2
votes
0
answers
1k
views
Advanced texts on analytic number theory?
So a friend of mine is very interested in analytic number theory, and is looking for resources past the basic level.
He has studied analytic number theory from several books, among them are Hardy’s ...
3
votes
0
answers
221
views
Reference request Re Vinogradov's ternary Goldbach proof
I believe that I.M. Vinogradov's proof of the ternary Goldbach conjecture used the observation that the number of ways $n$ can be written as a sum of three primes equals
$$
\int_0^1 \sum_{p , q , r \...
4
votes
0
answers
272
views
The Gamma-transform and $p$-adic $L$-functions
I'm currently reading the paper "On the $\mu$-invariant of the $\Gamma$-transform of a rational function" by W Sinnott. In this paper, he gives an alternate proof that $\mu=0$ for abelian ...
3
votes
1
answer
251
views
Congruence modulo 2 for q-series
This quest arose from certain calculations with integer partitions (having distinct parts) and the corresponding values of their Dyson ranks.
I would like to ask:
QUESTION. Is this congruence true ...
-1
votes
1
answer
162
views
Convergence to a constant or not? Reference request [closed]
Consider the function
$$f(n) = \log n /(n\ \log\theta(p_n)),$$
where $\theta$ is the first Chebyshev function and $p_n$ is the $n$-th prime. Does $f$ converge to a constant as $n$ grows to infinity, ...
0
votes
0
answers
196
views
Sum of squares squared in an arithmetic progression
Let $r(n)$ be the number of ways to write $n$ as a sum of two squares and $(a,q)=1$.
What is known about
$$
\sum_{n \le x,n \equiv a (\text{mod} \, q)} r(n)^2 \quad?
$$
I am looking for uniform ...
4
votes
1
answer
462
views
Generalizations of the Brun-Titchmarsh theorem
Let $\pi(x;q,a)$ count the number of primes $\leq x$ congruent to $a$ mod $q$. The Brun-Titchmarsh Theorem states that for all $q< x$, $(a,q)=1$, we have
$$
\tag{1}
\pi(x;q,a) \leq \frac{2x}{\...
3
votes
1
answer
418
views
Counting cubic residues mod p
Given a prime $p=3m+1$, $(p-1)/3$ of the residues mod $p$ are cubic residues. So heuristically, for any given integer $k>1$ not a perfect cube, we would expect that about 1/3 of the primes $\equiv1\...
2
votes
0
answers
150
views
Closeness of a rational approximation
What is
$$p_*:=\inf\big\{p\in\mathbb R\colon\,\inf_{n\in\mathbb N}n^p\,\inf_{k\in\mathbb N}
|2\sqrt{3n}-9\pi/4-k\pi|>0\big\},$$
where $\mathbb N:=\{1,2,\dots\}$?
In other words, I would like to ...
4
votes
1
answer
233
views
About colossally abundant numbers - reference request
This post contains three related questions:
In the OEIS sequence 073751 ( https://oeis.org/A073751/ ) there is a short Mathematica program that is said to produce the prime factors of successive ...
1
vote
0
answers
192
views
Uniform distribution mod $1$ vs independence of random variables
Let $a_1, \cdots, a_k \in [0, 1)$ be real numbers such that $1, a_1, \cdots, a_k$ are independent over the rational numbers. By the Weyl equidistribution criterion in $k$-dimensions, we know that the ...
4
votes
1
answer
206
views
Relative density of primes in certain congruence classes
In "M. B. Nathanson - Elementary Methods in Number Theory" is shown (Theorem 7.14) that if $A$ is a set of positive integers such that $\sum_{a \in A} 1 / a$ converges then the set of ...
4
votes
1
answer
263
views
A refinment of Beck's conjecture
Let $\mathcal{O}(n)$ and $\mathcal{D}(n)$ denote the set of all integer partitions of $n$ into odd parts and distinct parts, respectively. Let $o(n)=\#\mathcal{O}(n)$ and $d(n)=\#\mathcal{D}(n)$. ...
1
vote
1
answer
186
views
Connection between central factorial numbers and the Stern–Brocot tree
Consider the central factorial numbers of even indices formed by
$$U(n,k)=\frac1{(2k)!}\sum_{i=0}^{2k}(-1)^i\binom{2k}i(k-i)^{2n}.$$
Let $u(n,k):=U(n,k)\mod 2$. Define the triangle of numbers
$$A(r,j)=...
5
votes
1
answer
210
views
Results using a certain kind of identity
Recently, I've been reading about asymptotics for smooth numbers as well as smooth numbers in arithmetic progressions. One of the ideas I find especially pleasing among some of these results is the ...
0
votes
0
answers
157
views
On the mean value of Dirichlet L-function
Could you please provide a link to the source?
$$\sum_{\chi\neq \chi_0}\int_{0}^{T}|L(1/2+it,\chi)|^4dt\ll (qT)^{1+\varepsilon},$$ where $\chi_0$ is the principal character modulo $q$, and $L(s,\chi)$ ...
4
votes
1
answer
271
views
The highest power of $2$ dividing a polynomial evaluated at $x=3$
Let $\nu_2(a)$ be the $2$-adic valuation of an integer $x$, i.e. the largest power $t$ such that $2^t$ divides $x$.
Define the operator $D=x\frac{d}{dx}$ and the polynomial $\Phi_k(x)=\frac{x^{k+1}-1}{...
1
vote
0
answers
229
views
A sum involving the Jacobi symbols
Let $n>1$ be an odd integer and let $(\frac{\cdot}{n})$ be the Jacobi symbol. For an integer $a$, define
$$S_a=\sum_{x=0}^{n-1}\left(\frac{x^2-a^2}{n}\right).$$
Are there any results on the ...
14
votes
1
answer
424
views
Unpublished result of Rosser in Sieve Methods book
Erdős and Selfridge (1971) state that the following is "implied by an unpublished result of Rosser" which they claim appears in a forthcoming book on sieve methods by Halberstam and Richert.
...
2
votes
0
answers
115
views
Reference request: "A result of Siegel" related to Ramanujan-Nagell type equations
Wikipedia refers to the Diophantine equation
$ x^2 + D = AB^n $
as an "equation of Ramanujan–Nagell type". It also says that "A result of Siegel implies that the number of solutions in ...
9
votes
0
answers
462
views
Who realized the finite fields $\mathbb F_{p^n}$ first? Gauss or Galois?
Let $p$ be a prime, and let $n$ be a positive integer. The finite field $\mathbb F_{p^n}$ is often called a Galois field and denoted by $\mathrm{GF}(p^n)$ by researchers on coding theory.
On the other ...
18
votes
2
answers
3k
views
Only odd primes?
For $k \ge 2$, let
$$u = \{\lfloor{(k - \sqrt{k})n}\rfloor : n \ge 1\}$$
$$v = \{\lfloor{(k + \sqrt{k})n}\rfloor : n \ge 1\}.$$
My computer suggests that $u$ and $v$ are disjoint if and only if $k$ is ...
4
votes
1
answer
239
views
Yet, another numerical variant of the Vandermonde matrix
In my earlier (soft) MO post, an elementary response was given by Ofir Gorodetsky in regard to the determinant of the symbolic counterpart to the numerical matrix $\mathbf{M}_n=(i^j-j^i)_{i,j}^{1,n}$.
...
2
votes
1
answer
413
views
Resources and outstanding conjectures about the Epstein zeta function
I am looking for a reference to the Epstein zeta function. For the Riemann zeta function, there is Titchmarsh's treatment. However, I do not know of any references regarding the Epstein zeta function ...
4
votes
0
answers
186
views
A problem in the spirit of P. Borwein's polynomials
A well-known conjecture (now a theorem) of P. Borwein (see Wang and Krattenthaler - An asymptotic approach to Borwein-type sign pattern theorems) states:
For all positive integers $n$, the sign ...
1
vote
0
answers
84
views
Sum of fractional parts over coprime residues
Let $q$ be a positive integer and $\theta$ a real number with $0 \leq \theta < 1$. Consider the two sums
$$
S_\theta^\pm(q)=\sum_{\substack{r=1\\ (r,q)=1}}^{q-1} \left\{\theta\pm\frac{r}{q} \right\}...
10
votes
2
answers
849
views
Schur's proof of Hilbert's inequality: streamlining?
TL;DR: Is there a way to make Schur's (elegant) proof of Hilbert's inequality feel like
less of a trick/miracle?
Longer version: Let me go quickly over Schur's proof to show what I mean. Actually, let ...
3
votes
1
answer
200
views
Maximum number of edges in a "coprime graph"
Let's define a coprime graph as a simple graph (undirected graph without any self-loops or multiple-edges) in which for all edges $(𝑢, 𝑣)$, the property $\gcd(\mathrm{degree}_u, \mathrm{degree}_v) = ...
0
votes
1
answer
180
views
Name of conjectures similar to Goldbach conjecture
Consider the following """easier""" conjectures:
C1. every sum of two semiprimes $n = pq + rs$, $p,q,r,s$ primes, can be expressed as $n = (a + b)/2$; with $a,b$ primes.
...
-2
votes
1
answer
139
views
Congruence modulo 4 for a generating function leads to perfect squares? [duplicate]
Consider the number of integer partitions $p(n)$ of $n$ whose generating function is
$$\sum_{n\geq0}p(n)\,x^n=\prod_{k\geq1}\frac1{1-x^k}.$$
Also, the number of partitions into distinct parts $Q(n)$ ...
4
votes
0
answers
214
views
Maximum entropy methods for probabilistic number theory
Might there be a good survey paper on the application of maximum entropy inference for non-trivial problems in probabilistic number theory?
So far I am aware of the work of Ioannis Kontoyiannis, an ...
1
vote
1
answer
344
views
Is there a way to tie up even and "newly suggested odd" Riemann zeta values?
Define the sequence
$$a_s=(-1)^{\binom{s-1}2}\left(\frac{\pi}2\right)^s\frac1{2\cdot s!}\begin{cases} s\,E_{s-1}, \qquad \text{if $s$ is odd} \\ 2^{2s}B_s, \qquad \,\,\text{if $s$ is even};\end{cases}$...
1
vote
0
answers
159
views
A follow up on Bergeron's conjecture and a question
We say two polynomials satisfy $P(x)\geq Q(x)$ iff $P(x)-Q(x)$ has non-negative coefficients. Recall $(n)_q!=\prod_{j=1}^n(1-q^j)$ and the Gaussian polynomials $\binom{n}k_q=\frac{(n)_q!}{(k)_q!(n-k)...
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 ...
2
votes
3
answers
742
views
Asking for a proof for a sum of products of binomials: an "interesting" identity?
The following identity must have received alternative proofs, including a combinatorial argument by David Callan as found at Bijections for the Identity $4^n = \sum_{k = 0}^n \binom{2k}k\binom{2(n - k)...
3
votes
1
answer
248
views
number of integers $n$ with $\|n \alpha \|$ small?
Let $\alpha \in \mathbb{R}$ and $N$ a positive integer. I am interested in the quantity
$$
D(\alpha, N) := \# \{ n \in [1, N]: \| n \alpha \| < 1/N \},
$$
$\| x \|$ denotes the distance to the ...