Questions tagged [euler-product]
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37
questions
-2
votes
1
answer
115
views
Convergence of scrambled product for Dirichlet-$L$ function with modulo 4 character
A Dirichlet-$L$ function is typically defined by its series, and its Euler product is a consequence of the definition. Here my approach is the other way around.
I define the function
$$
L_4^*(s) = \...
1
vote
2
answers
281
views
Abscissa of convergence for a very specific Dirichlet series / Euler product
I am interested in the convergence of the following Euler product:
$$
\prod_p \frac{1}{1-\chi(p)\cdot p^{-s}}.
$$
The product is over all primes (in increasing order), with $\chi(p)=+1$ if $p \bmod 4 =...
1
vote
0
answers
193
views
Convergence of zeta Euler product with additional term
Let's consider the following Euler product ($s=\sigma+it)$:
$$ P(s)=\prod_{p \; \text{prime}} \frac{1}{1-p^{-s}} \; e^{-p^{-s}}$$
So for $\sigma>1$, it is clear the product converges and we have:
$$...
2
votes
1
answer
262
views
Pólya–Vinogradov like inequality for a character sum with Euler factors
Let $M$ be a large positive integer, $d$ an odd positive integer and $f: \mathbb{Z}_{>0} \times \mathbb{Z}_{>0} \to \mathbb{R}$. For a non-principal character $\chi_d = \chi$ with modulus $d$, I ...
1
vote
1
answer
133
views
Sum of an arithmetic sequence involving Euler factors
I am trying to find an asymptotic formula for the following sum as $T \to \infty$.
$$ \sum_{t = 1}^{T} \prod_{\substack{p \; \textrm{prime} \\ p | t}} \rho(p) \frac{1 - \frac{1}{p^2}}{1 - \frac{\rho(p)...
6
votes
2
answers
1k
views
On modified Euler product
Consider the modified Euler product as follows:
$$F(s) = \prod_{p} \left( 1 - \frac{c}{p^s} \right)^{-\ln(p)}$$
Here $c$ is a constant
My questions are
Is there a compact representation for this ...
2
votes
2
answers
591
views
Convergence of Euler product and Dirichlet series in the same half-plane?
I'm crossposting this from math.stackexchange because I think it might be inappropriately research-level for the community over there.
Suppose we have an Euler product over the primes
$$F(s) = \prod_{...
18
votes
1
answer
665
views
Could computing the next prime in a finite Euler product be made rigorous?
It is well known that:
$$\zeta(s):=\prod_{n=1}^{\infty} \frac{1}{1-p_n^{-s}} \qquad \Re(s) \gt 1$$
with $p_n =$ the $n$-th prime. It also known that:
$$\zeta(2n):= \frac{(-1)^{n+1} B_{2n}(2\pi)^{2n}}{...
1
vote
0
answers
149
views
Euler product over subsets of primes
It is well known that
$$\prod_p\,(1-p^{-1})=\frac 1 {\zeta(1)}=0$$
Given an arbitrary prime $\,q\,$ is it true that
$$\prod_{q\,|\,p+1}\,(1-p^{-1})=0\;\;\;?$$
Thanks.
1
vote
0
answers
135
views
What is behind the constant in the functional equation for the Hasse-Weil zeta function?
Let $X_0$ be a smooth projective variety over $\mathbf{F}_q$ of dimension $n$. The Weil conjectures assert that the zeta function $Z(X_0,t)$ satisfies the functional equation
$$Z(X_0,t) = \pm q^{\...
-3
votes
2
answers
260
views
The inequality $\Pi (1-\frac{1}{a_i})^{x_i} \le \Pi (1-\frac{1}{b_j})^{y_j} $ hold? [closed]
Question: Are the properties as follows holds?
Version 1: the answer by Bjørn Kjos-Hanssen
Let $P$ be a positive integers. We written: $P=$ $a_1^{x_1}a_2^{x_2}...a_n^{x_n}$ $=b_1^{y_1}b_2^{y_2}......
3
votes
1
answer
277
views
Reference request for Euler products in positive characteristic
Let $K$ be a global field with ring of integers $O$, and let $f$ some integer valued function whose domain is the set of ideals of $O$ (e.g. $f(I)=|O:I|$). Extending the ordinary definition from the ...
2
votes
0
answers
76
views
Accelerating convergence of a product by multiplying by zeta values: history?
Let $R(s_1,\dotsc,s_n) = \prod_p r(p^{-s_1},\dotsc,p^{-s_n})$, where
$r$ is a rational function on $n$ variables. Say we want to compute the value of $R(s_1,\dotsc,s_n)$ for some choice of $s_1,\dotsc,...
11
votes
1
answer
240
views
Partial product of Euler factors
Let $\mathbb P$ denote the set of prime numbers and for a subset $T\subset \mathbb P$ let
$$
\zeta_T(s)=\prod_{p\in T}\frac1{1-p^{-s}},
$$
where $\mathrm{Re}(s)>1$.
Is there any $T$ such that $T$ ...
1
vote
0
answers
69
views
Some theoretical question on Euler product
It is very rare that the Euler product
\[
\lim_{X \to \infty}\prod_{p \leq X}(1 + a(p)p^{-s})
\]
conditionally converges for $\sigma > A$ with some $0 < A \leq 1$
when $|a(n)| = 1$.
Suppose ...
0
votes
1
answer
276
views
Analytic continuation of Euler product $\prod_{p} (1 - e^{-2 \pi i p \alpha}p^{-s})^{-1}$
Is anything useful known about the function defined by
\[
f(s, \alpha) = \prod_{p} (1 - e^{-2 \pi i p \alpha}p^{-s})^{-1} \quad ?
\]
Here, $\alpha$ is real. When $\alpha = 1$, this is certainly the ...
1
vote
0
answers
138
views
Euler products without meromorphic continuation
For every prime number $p$ fix a natural number $n_p$ with
$$
C\frac{p+1}2\le n_p\le C(p+1)
$$
for some constant $C>0$, independent of $p$.
The product
$$
F(s)=\prod_p\frac1{(1-p^{-s})^{n_p}}
$$
...
2
votes
0
answers
142
views
Interchanging limit and infinite product in Euler product for Dedekind function s=1
For an quartic (non-Galois) CM-field $K$ I have factors $v_p$ and for every prime $p$ found the following relation
$$v_p={\frac {\prod_{\mathfrak{p}|p;\mathfrak{p}\subset\mathcal0_{K}}(1-N_{{K/{\...
11
votes
2
answers
1k
views
Does this product have analytic continuation?
The product
$$
F(s)=\prod_{p}\frac1{(1-p^{-s})^p},
$$
converges for $\mathrm{Re}(s)>2$, when $p$ runs over all primes. Does it admit analytic continuation beyond the line $\mathrm{Re}(s)=2$? Any ...
1
vote
1
answer
375
views
What is the Euler product for double summations?
I know that the Euler product of a summation of multiplicative function is given by
$$\sum_nf(n)=\prod_p (1+f(p)+f(p^2)+....),$$
and if we have the Möbius function then it will be
$$\sum_n\mu (n)...
4
votes
2
answers
994
views
Riemann Hypothesis and Euler product
It is conjecture that under certain conditions a L-function satisfies RH.
Among these conditions there is the necessity for the L-function to have an Euler product. (Some L-functions with a functional ...
3
votes
0
answers
391
views
Generalization of Trigonometric, Hyperbolic, $\Gamma$ and $\zeta$ Functions
It is becoming increasingly clear that the expression $~\displaystyle\prod_{n\in\mathbf M}\left[1-\frac{z^s}{(n-a)^s}\right],~$ with $~|\mathbf M|=\aleph_0,~$
$a\not\in\mathbf M,~$ and $~\Re(s)>1,~$...
5
votes
1
answer
412
views
If a Dirichlet series converges Conditionally, how can I apply Euler product?
In 1737, Euler discovered that if $ f(n) $ is multiplicative and $ \sum f(n)/n^{s} $ converges absolutely for ${\rm Re}(s) > \sigma_a$ then we have
\begin{equation}
\sum_{n=1}^{\infty} \frac{f(n)}{...
1
vote
0
answers
180
views
Convergence of the Mellin transform of $\zeta(s)\, \Gamma(s)$ for line integrals with real part $\le 1$
This question is inspired by this one, however I believe is quite different.
The Mellin transform for:
$$\displaystyle \Gamma(s)\,\zeta(s)= \int_0^\infty x^{s-1} \frac{1}{e^x-1}\,dx$$
equals:
$$\...
1
vote
0
answers
140
views
Behavior of partial Euler product in the critical strip (with Dirichlet Character)
Consider a primitive Dirichlet Character $\chi$ (non principal) and the partial Euler product attached to the L-function $L(\chi,s)$ ($p_i$ are the prime numbers) :
$$P(\chi,N)=\prod_{i=1}^{N} \frac{...
3
votes
0
answers
139
views
Square integral of finite Euler product
Consider the finite Euler product
$$
P(t) = \prod_{r=1}^R \left(1 + p_r^{i t} \right).
$$
(Here $p_1, p_2, \dots$ are of course the primes.)
Question: What is a good asymptotic upper bound for
$$
\...
7
votes
2
answers
763
views
How do i show that:$\prod\frac{p^2+1}{p^2-1}=\frac{5}{2}$ without using properties of Riemann zeta function? [duplicate]
In order to know more about product over primes ,I would like to know how do I show that :$$\prod\frac{p^2+1}{p^2-1}=\frac{5}{2}$$ without using properties of Riemann zeta function ?
Note01 : it ...
3
votes
1
answer
685
views
Euler product for sum of multiplicative function times log
(Cross-posted from StackExchange). Let $g$ be a multiplicative function which satisfies $0 \le g(p) \ll 1/p$ and
$$ \sum_{p\le x} g(p) = \log \log x + C + O((\log x)^{-10}). $$
Iwaniec and ...
6
votes
2
answers
381
views
Does the limit of this product over primes converge for all $\Re(s) > \frac12$?
Numerical evidence suggests that:
$$\displaystyle F(s):= \lim_{N \to \infty}\, \ln^s\left(p_N\right)\, \prod_{n=1}^N \left(\dfrac{\left(p_n-1\right)^s}{p_n^s-1} -\frac{1}{p_n^s}\right)$$
with $p_n$ ...
8
votes
0
answers
395
views
Arithmetic zeta function and local zeta functions
For the arithmetic zeta function of (say) a nonsingular projective variety $X$, one has the following Euler product
\begin{equation}
\zeta_X(s) = \prod_{p\ \mbox{prime}}\zeta_{X\vert\mathbb{F}_p}(s),
...
1
vote
0
answers
145
views
An apparent closed form for a slightly tweaked Dirichlet L-function. Could it be proven? [closed]
I made a small tweak to the well-known Dirichlet L-function ($p$=prime):
$$L(s, \chi_4) :=\prod_p \bigg(\frac {p^s}{p^s-\chi_4(p)} \bigg)=\prod_p \bigg(\frac {p^s}{p^s-\sin\left(\frac{p \,\pi}{2}\...
5
votes
1
answer
929
views
Does the Euler product for $L(s,\chi_4)$ also converge in the right half of the critical strip?
This question expands on this one from MSE.
In the literature about Dirichlet $L$-series, I found that their Euler products:
$$L(s, \chi) =\prod_p \bigg(\frac {1}{1-\frac{\chi(p)}{p^s}} \bigg)$$
...
4
votes
2
answers
586
views
Do the roots of this equation involving two Euler products all reside on the critical line?
This question loosely builds on the second part of this one.
Take the Riemann $\xi$-function: $\xi(s) =\frac12 s\,(s-1) \,\pi^{-\frac{s}{2}}\, \Gamma\left(\frac{s}{2}\right)\, \zeta(s)$. Numerical ...
1
vote
0
answers
166
views
Existence of Euler product on critical line for $L(\chi,s) L(\overline{\chi},1-s)$?
Generally there is no Euler product for Dirichlet L-functions $L(\chi,s)$ in the critical strip.(cf Is the Euler product formula always divergent for 0<Re(s)<1?)
But I would like to know if ...
0
votes
1
answer
777
views
Euler product of Asai L-function?
Let $\pi$ be an automorphic form of GL(n)/$\mathbb{Q}$ with standard $L$-function
$$L(s,\pi)=\prod_p \prod_{i=1}^n(1-\frac{\alpha_{p,i}}{p^s})^{-1},$$
where $\{\alpha_{p,i}:i=1,\dots,n\}$ are the ...
6
votes
3
answers
980
views
Does this 'alternating' Euler product converge for all $\Re(s) > 0$?
Does the following 'alternating' Euler product, with $p_n$ the $n$-th prime number, converge for $\Re(s)>0$ ?
$$\displaystyle \prod_{n=1}^\infty \left( \dfrac{1}{1-\frac{1}{p_{n}^{s}}} \right)^{(...
1
vote
0
answers
98
views
Question about the zeros of the sum/difference of two finite Euler products
The conjecture Are all zeros of $\zeta(0+s) \pm \zeta(0-s)$ except a finite few on the line $\Re(s)=0$? was shown to be unconditionally true.
The proof can even be extended towards the domain $\...