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9 votes
1 answer
430 views

$2$-adic valuations: a tale of two $q$-series

Let $\nu_p(n)$ denote the $p$-adic valuation of $n$, i.e. the highest power of $p$ dividing $n$. Consider the following two $q$-series formed by infinite products $$\prod_{n\geq1}\left(\frac{1+q^n}{1-...
T. Amdeberhan's user avatar
2 votes
0 answers
490 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 ...
Yuji Tachikawa's user avatar
6 votes
2 answers
547 views

2-adic valuation of a certain binomial sum

Consider the sequence (of rational numbers) given by $$a_n=\sum_{k=1}^n\binom{n}k\frac{k}{n+k}.$$ Let $s(n)$ be the sum of binary digits of $n$, i.e. the total number of $1$'s. QUESTION. Is it true ...
T. Amdeberhan's user avatar
6 votes
1 answer
183 views

Mean value of the divisor function over Piatetski-Shapiro sequences

Let $c>1$, $c\not\in\mathbb{Z}$ and consider the sum $$ \sum_{n\leq x} \tau(\lfloor n^c \rfloor), $$ where $\tau(n)$ is the number of divisors of $n$. I'm almost certain I've seen an evaluation of ...
Joshua Stucky's user avatar
3 votes
1 answer
758 views

Looking for a paper of Lagarias and Odlyzko

I have been studying about the Chebotarev Density Theorem and have been hunting for the following paper of Lagarias and Odlyzko for quite a while: Effective versions of the Chebotarev density theorem, ...
asrxiiviii's user avatar
25 votes
8 answers
3k views

Relatively concise English expositions of the proofs of the various Weil conjectures

Where can I find relatively concise (i.e. not excessively wordy and waxing poetic about history and intuitions and such, doesn't spend an eternity carefully developing various parts of the theory of ...
user avatar
1 vote
1 answer
153 views

Number of distinct near-squares primes dividing an odd perfect number

I'm curious about if the following question is in the literature or what work can be done about it. Denote the number of distinct primes dividing an odd perfect number $N$ with the arithmetic function ...
user142929's user avatar
3 votes
1 answer
228 views

What fraction of the values of a quadratic polynomial can be prime?

I have an explicit, monic quadratic polynomial $P(x)$ and an integer $m$. Can I bound the number of prime values in $P(0), P(1), \ldots, P(m)$? A reference would be appreciated, if available. An ...
Charles's user avatar
  • 9,114
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 ...
Johnny T.'s user avatar
  • 3,625
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 ...
1 vote
1 answer
220 views

Gaussian at $q=\pm1$, log-concave polynomials, Catalan numbers

Let $[n]_q!=\prod_{j=1}^n\frac{1-q^j}{1-q}$ with $[0]_q!:=1$ and the Gaussian polynomials $\binom{n}k_q=\frac{[n]_q!}{[k]_q!\,\cdot\,[n-k]_q!}$. Adopt the convention that $\binom{n}k_q=0$ whenever $k&...
T. Amdeberhan's user avatar
11 votes
1 answer
699 views

Are the L-functions of a normalized newform and the corresponding cuspidal representation equal?

Let $f \in S_k(\Gamma_0(N))$ be a normalized newform with Fourier expansion $$f(z) = \sum\limits_{n=1}^{\infty} a_n e^{2\pi i z n}$$ and $a_1 = 1$. Then $f$ is an eigenfunction of all Hecke ...
D_S's user avatar
  • 6,180
3 votes
1 answer
182 views

$l$-adic sheaf associated to an algebraic representation of $\mathrm{GSp}_{4}(\mathbb{Q})$

Let $Y (N) $ be the moduli scheme of dimension two principally polarized Abelian schemes with level $N$. It is claimed in "G.Laumon - Fonctions zeta des variétés de Siegel" (Lemma 4.1) that ...
Marsault Chabat's user avatar
3 votes
2 answers
335 views

Reference where the Siegel-Walfisz theorem for the Möbius function is proved

Let $A>0$ and $q\leq (\log N)^A$. Then there exists a constant $c$ depending on $A$ such that $\displaystyle \sum_{n\equiv a \bmod q; n\leq N}\mu(n)\ll N\exp(-c\sqrt{\log N})$. I know this result ...
user avatar
4 votes
1 answer
246 views

Is $C_n$ infinitely log-convex?

A sequence $a_n$ is called log-convex if $\mathcal{L}(a_n):=a_{n+1}a_{n-1}-a_n^2\geq0$ for all $n$; it is infinitely log-convex provided that all the iterates $\mathcal{L}^k(a_n)$ are still log-convex,...
T. Amdeberhan's user avatar
12 votes
2 answers
1k views

Short research articles

I am a masters student. I am interested in short articles which have counter examples and very few references. I want to write a short and interesting article. For example; One of the best known ...
27 votes
3 answers
3k views

Where's the best place for an algebraic geometer to learn some algebraic number theory?

There are lots of introductions to number theory out there, but typically they are streamlined to assume as little prerequisite knowledge as possible. I'm looking for a text which does the opposite -- ...
Tim Campion's user avatar
4 votes
2 answers
593 views

Squares in Lucas sequences

Good night, everyone! According to a celebrated result by J. H. Cohn, the only perfect squares in the Fibonacci sequence are $F_{0}=0$, $F_{1}=F_{2}=1$, and $F_{12}=144$. It is also known that the ...
Jamai-Con's user avatar
4 votes
1 answer
700 views

Total sum of characters of the symmetric group $\frak{S}_n$

Let $\chi_{\mu}^{\lambda}$ denote a value of an irreducible character of the symmetric group $\frak{S}_n$, where $\mu, \lambda\vdash n$. When $\mu=(n)$, then it's known that $$\sum_{\lambda\vdash n}\...
T. Amdeberhan's user avatar
1 vote
1 answer
177 views

Distribution of $\alpha n^2/q$ modulo $1$?

Let $0 \neq \alpha \in [0,1]$ and $q$ a positive integer. Let $||.||$ denote the distance to the closest integer and define $$ N_i(q) = \sum_{ \substack{ -q/2 \leq n \leq q/2 \\ \frac{i}{q} \leq || \...
Johnny T.'s user avatar
  • 3,625
7 votes
3 answers
826 views

Analytic equivalents for primes in arithmetic progressions

By way of context: it is known that the prime number theorem $\pi(x) \sim x/\log x$ is (nontrivially) equivalent to the statement that $\zeta(s)$ does not vanish on the line $\Re s=1$. I would like ...
Greg Martin's user avatar
  • 12.8k
17 votes
2 answers
1k views

The GCD-matrix: generalizing a result of Smith?

Let $M$ be the $n\times n$ matrix, known as the GCD matrix, of entries $M_{ij}=\gcd(i,j)$. In the paper H J S Smith, On the value of a certain arithmetical determinant, Proc. London Math. Soc. 7:208-...
T. Amdeberhan's user avatar
23 votes
1 answer
3k views

A list of proofs of the Hasse–Minkowski theorem

I am currently doing a project in which I intend to include the most insightful possible proof of the Hasse–Minkowski theorem (also known as the Hasse principle for quadratic forms, among other names) ...
14 votes
1 answer
749 views

reference for: no finite set of positive (integer) binary quadratic forms represents all primes

This recent question asks for a set of forms (binary quadratic) representing all primes. Set of quadratic forms that represents all primes When the question was asked on MSE last month https://math....
Will Jagy's user avatar
  • 25.7k
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 $\mathbf{M}_n=(i^j-j^i)_{i,j}^{1,n}$. ...
T. Amdeberhan's user avatar
30 votes
2 answers
4k views

Motivation behind Analytic Number Theory

I am an undergraduate student of mathematics and recently took an introductory course in analytic number theory, where the instructor roughly followed Apostol's first text on the subject. I have now ...
user135845's user avatar
2 votes
0 answers
182 views

On the relative class number of a cyclotomic extension

Let $\Bbb Z[\zeta_p]$ denote the cyclotomic integers where $p$ is a prime and let $h_1 = h_1(p)$ denote its relative class number. Question: Is it known whether there are infinitely many primes $p$ ...
John Klein's user avatar
  • 18.9k
3 votes
0 answers
115 views

Counting monomials modulo prime numbers

The present quest emanates from this study by R. Stanley, including his recent MO question. Define the product (polynomials after full expansion) $$I_n(x)=\prod_{i=1}^n(1+x^{F_{i+1}})$$ based on the ...
T. Amdeberhan's user avatar
29 votes
4 answers
5k views

What is Ricardo Pérez-Marco's eñe product? Does it explain his statistical results on differences of zeta zeros?

The number theory community here at University of Michigan is abuzz with talk of this paper recently posted to the arxiv. If you haven't seen it already, the punch line is that the global differences ...
Gene S. Kopp's user avatar
  • 2,210
13 votes
3 answers
1k views

linear independence of $\sin(k \pi / m)$

I have tried searching the literature for a result like the following, but have not found anything. For a positive integer $m$, is it known that $$\{ \sin (k \pi / m): 1 \leq k \leq m/2, (k,m)=1 \}$$ ...
user95204's user avatar
  • 133
13 votes
1 answer
601 views

Congruences for "colored partitions" a la Ramanujan

Let $t\in\Bbb{N}$ and consider the sequences $p_t(n)$ defined by $$\sum_{n\geq0}p_t(n)x^n=\prod_{i\geq1}\frac1{(1-x^i)^t}=(x;x)_{\infty}^{-t}.$$ The numbers $p_t(n)$ can be regarded as enumerating ...
T. Amdeberhan's user avatar
9 votes
1 answer
638 views

Algebraic independence of $P,Q,R$ or $E_2,E_4,E_6$ over $\mathbb C(z)$

Let $P,Q,R$ be the Fourier series of the Eisenstein series $E_2,E_4,E_6$, that is, $$ P(q)=1-24\sum_{n=1}^{\infty}\sigma_1(n)q^n, $$ $$ Q(q)=1+240\sum_{n=1}^{\infty}\sigma_3(n)q^n, $$ $$ R(q)=1-504\...
LWW's user avatar
  • 663
9 votes
1 answer
574 views

Innovations in number theory leading to breakthroughs in statistical mechanics

Might there be a good reference on the interaction of number theory with statistical physics? I am particularly interested in innovations in number theory that have led to breakthroughs in statistical ...
Aidan Rocke's user avatar
  • 3,871
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 $d(n)=\#\mathcal{D}(n)$. ...
T. Amdeberhan's user avatar
5 votes
1 answer
264 views

Analogue of the second Hardy-Littlewood conjecture for numbers of divisors?

Let $f(n)$ denote the proposition "There exists some $k>1$ such that $$ \sum_{m=k}^{k+n-1}\tau(m) < \sum_{m=1}^n\tau(m) $$ where $\tau(m)$ is the number of the divisors of $m$." (This ...
Charles's user avatar
  • 9,114
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 ...
user859588's user avatar
11 votes
1 answer
2k views

Reference request: proof of Ramanujan's Cos/Cosh Identity

The Ramanujan Cos/Cosh Identity, as stated here, is $$\left[1+2\sum_{n=1}^{\infty}\frac{\cos n\theta}{\cosh n\pi}\right]^{-2}+ \left[1+2\sum_{n=1}^{\infty}\frac{\cosh n\theta}{\cosh n\pi}\right]^{-2}=...
Descartes Before the Horse's user avatar
1 vote
0 answers
98 views

Reference request for a result in additive combinatorics

Let $p$ be a prime number and $[p-1]=\{1, 2, \ldots, p-1\}$. The following proposition is proved: (but I cannot find out where) Proposition: The non-empty subset sums of $[p-1]$ are equally ...
Konstantinos Gaitanas's user avatar
5 votes
1 answer
435 views

Limit on a certain double sum

While working with multi-zeta functions, I encountered the below (experimental) value for a certain evaluation (in a limit sense). Notice first this well-known fact in context $$\sum_{n,m\geq1}\frac1{...
T. Amdeberhan's user avatar
7 votes
1 answer
303 views

on a strange character sum

Recently while studying cubic residues modulo a prime $p$ with $p\equiv1\pmod 3$, I met the following character sum: $$\sum_{0\le x\le p-1}\left(\frac{x}{p}\right)\left(\frac{x+1}{p}\right)\left(\frac{...
CNT's user avatar
  • 93
6 votes
4 answers
901 views

Mathematical induction vis-à-vis primes

One of the most used proof-techniques is mathematical induction, and one of the oldest subjects is the study of prime numbers. Thanks to Euclid, we can consider the primes as a infinite monotone ...
8 votes
2 answers
396 views

De Bruijn's sequence is odd iff $n=2^m-1$: Part I

Among the families of sequences studied by Nicolaas de Bruijn (Asymptotic Methods in Analysis, 1958), let's focus on the (modified) $$\hat{S}(4,n)=\frac1{n+1}\sum_{k=0}^{2n}(-1)^{n+k}\binom{2n}k^4.$$ ...
T. Amdeberhan's user avatar
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 ...
EGME's user avatar
  • 1,018
9 votes
2 answers
709 views

Egyptian number theory

Might there be a good historical reference on Egyptian number theory ($ \sim 2000$ B.C.)? The following online reference by a professor at the UCLA indicates that they were aware of the Pythagorean ...
Aidan Rocke's user avatar
  • 3,871
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}$...
T. Amdeberhan's user avatar
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 ...
Hhhhhhhhhhh's user avatar
  • 1,042
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 ...
T. Amdeberhan's user avatar
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}{...
T. Amdeberhan's user avatar
5 votes
2 answers
307 views

Modulo $3$ calculations for a binomial-sum sequence

Introduce the sequence (this is A047781 on OEIS) $$t_n=\sum_{k=0}^{n-1}\binom{n-1}k\binom{n+k}k$$ and denote the set $T(ij)=\{n\in\mathbb{N}: \text{the ternary digits of $n$ contain $i$ or $j$ only}\}$...
T. Amdeberhan's user avatar
4 votes
1 answer
298 views

Enumeration of dominated Dyck paths

Using horizontal steps $(1,0)$ and vertical steps $(0,-1)$, consider the lattice paths starting from $(0,q)$ and reaching $(p,0)$ with $p$ horizontal and $q$ vertical steps. The set of such paths $\...
T. Amdeberhan's user avatar

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