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3 votes
0 answers
164 views

Using the Hilbert symbol to find nice field extensions

Let $p$ and $q$ be (not necessarily distinct) odd primes and let $F=\mathbb{Q}_p(\mu_q)$. The $q^{th}$ Hilbert symbol induces a non-degenerate alternating form $$(\cdot,\cdot)_q:F^\times/(F^\times)^q\...
Spencer Leslie's user avatar
0 votes
0 answers
86 views

Polynomials of integer coefficients that evaluated at Mersenne or Fermat numbers produce square-free integers

Mersenne numbers $M_n=2^n-1$ and Fermat numbers $F_n=2^{2^n}+1$ draw the attention of professional mathematicians to get prime constellations or statements related to primality tests for these ...
user142929's user avatar
7 votes
1 answer
1k views

Beilinson's height pairing vs. Néron–Tate

In the literature there are several different definitions of what is often referred to as Beilinson's height pairing (see for example section 4.3.8 of Gillet and Soulé's paper Arithmetic intersection ...
Andreas Holmstrom's user avatar
1 vote
0 answers
69 views

Need help to check a quote from Hecke's "Lectures on Dirichlet Series, Modular Functions and Quadratic Forms"

I'd like to check the accuracy of a reference to Hecke's 1938 "Lectures on Dirichlet Series, Modular Functions and Quadratic Forms" implicit in eq. 4.8 on p. 50 of J. G. Leo's dissertation, which is ...
B. Brent's user avatar
4 votes
1 answer
545 views

class number of biquadratic fields

Can any one provide some references which treat the relation between the class number of a biquadratic field and the class numbers of its sub-fields using the analytic class number formula ?
Zakariae.B's user avatar
22 votes
2 answers
3k views

$p$-adic Langlands correspondence

Basic question: Is it correct that the $p$-adic Langlands correspondence is known for $GL_2$ only over $Q_p$ but not other $p$-adic fields? If so, I would like to request some light to be shed on this ...
SGP's user avatar
  • 3,867
3 votes
1 answer
270 views

Eisenstein series for discrete subgroups of SL(2,C)?

I am looking for a reference for Eisenstein series for discrete subgroups of $SL(2,\mathbb C)$, in particular, finite index subgroups of $SL(2,\mathcal O_K)$ where $K$ is an imaginary quadratic field. ...
Tian An's user avatar
  • 3,799
3 votes
0 answers
272 views

Reference request: Representing posets by integer divisibility

Does anyone know of an early published reference for the (very easy) fact that all finite posets can be represented as the poset of divisibility of a finite set of integers? Page 1 of Birkhoff's ...
David Eppstein's user avatar
18 votes
3 answers
745 views

Number of primitive $n$th roots with positive versus negative real parts

Does anyone know a reference to the following results, which I can prove, but I suspect may be known. Let $R(n)$ denote the number of primitive $n$th roots of unity with positive real part, and $L(n)$ ...
Glasby's user avatar
  • 1,991
16 votes
1 answer
706 views

Connection between Bernoulli numbers and Riemann-Siegel theta function?

I have come across a strange approximation for the Riemann-Siegel theta function involving the Bernoulli numbers - namely that $$\frac{1}{2} \log \left| B_{2 n}\right|\approx \vartheta (2n)\ ,\quad n ...
martin's user avatar
  • 1,903
5 votes
1 answer
1k views

Concrete bounds on the discriminant of a number field

There exists a well known concrete bound on the discriminant of a number field by Minkowski. Are there any concrete (completely explicit) improvements of this bound? I know of a bound by Odlyzko, ...
Pablo's user avatar
  • 11.3k
9 votes
1 answer
2k views

Sums of two squares in (certain) integral domains

While giving the first of eight lectures on introductory model theory and its applications yesterday, I stated Hilbert's 17th problem (or rather, Artin's Theorem): if $f \in \mathbb{R}[t_1,\ldots,t_n]$...
Pete L. Clark's user avatar
4 votes
2 answers
1k views

Primes $p$ for which $2p-1$ is prime

It's a well-known open problem (Sophie-Germain primes) whether there are infinitely many primes $p$, $2p+1$. What about $p$, $2p-1$? Seemingly it's also an open problem (see here and the linked ...
user236182's user avatar
8 votes
1 answer
247 views

Origin of definitions of ramified Hecke operators

Consider a classical space $M_k(N)$ of elliptic modular forms of weight $k$ for $\Gamma_0(N)$. The definition of an unramified Hecke operator $T_{p^m}$ in terms of double cosets is the disjoint union ...
Kimball's user avatar
  • 6,039
2 votes
2 answers
509 views

Question about Zeta Function of Singular Plane Curve

I am working on a project which involves learning about the zeta function (weil zeta function) for plane curves, but I do not know much algebraic geometry. (I do not know anything about schemes). I ...
maddels's user avatar
  • 53
7 votes
1 answer
487 views

Who proved the upper bound for the autocorrelation of higher order divisor functions?

Who first published a proof that $$\sum_{n\leq x}d_{k}(n)d_k(n+h)=O(x(\log x)^{2k-2})$$ for fixed $k$ and $h$ please? I am struggling to find a reference. Thank you.
Kevin Smith's user avatar
  • 2,480
5 votes
3 answers
417 views

Exact bin packing the harmonic series: references?

Given $n$ and $B_n= \lceil H_n \rceil$, where the latter is the $n$th harmonic number $\sum^n_{i=1} 1/i$, for most $n$ it is easy to pack the first $n$ terms of the harmonic series into $B_n$ many ...
Gerhard Paseman's user avatar
0 votes
0 answers
133 views

What about an alternative formulation for different prime constellations in the spirit of Suzuki's theorem for twin primes?

It is known that the twin prime conjecture is a special case of the $k$-tuple conjecture. See if you want the article with title k-Tuple Conjecture from the encyclopedia Wolfram MathWorld. On the ...
user142929's user avatar
6 votes
1 answer
288 views

Number of solutions for the inequality with square roots

Let $M$ be some large real number and $\delta>0$. I would like to estimate the number of solutions for the inequality $$|\sqrt{n_1}+\sqrt{n_2}-\sqrt{n_3}-\sqrt{n_4}|<\delta\sqrt{M},$$ where $...
Alexander Kalmynin's user avatar
7 votes
0 answers
379 views

Local properties of Galois representations attached to torsion classes

$\DeclareMathOperator{\PGL}{PGL} \DeclareMathOperator{\GL}{GL} \newcommand{\F}{\mathbb{F}} \newcommand{\p}{\mathfrak{p}} \DeclareMathOperator{\Sym}{Sym}$ Let $F$ be a number field, and let $\Gamma$ be ...
Aurel's user avatar
  • 5,382
3 votes
1 answer
276 views

Almost-Primes in Short Intervals

Let $S$ be the set of integers which are a product of $k$ distinct primes, $k$ a fixed positive integer (the condition that the primes are distinct is not crucial). Landau used the Prime Number ...
Ofir Gorodetsky's user avatar
7 votes
2 answers
708 views

Eisenstein Series on Siegel Space

I am looking for any reference dealing explicitly with Eisenstein series on Siegel space (the simplest case of $\rm{SP}_4$ is fine). Anything would be welcome, but in particular I'm interested in the ...
jacob's user avatar
  • 2,824
4 votes
0 answers
846 views

Reference request for a basic result on relative differents & discriminants

I am looking for a better reference for the results in this extremely short and elementary paper: Tôyama, Hiraku, `A note on the different of the composed field', Kōdai Math. Sem. Rep. 7 (1955), 43–44....
Bobby Grizzard's user avatar
3 votes
2 answers
411 views

When are "normal" functions normal?

I expected that the fractional part of f(n), n being an integer, would be distributed uniformly over [0,1] (for positive functions - otherwise take [-1,1]) for any run-of-the-mill function, except ...
Hauke Reddmann's user avatar
17 votes
1 answer
703 views

Combinatorics problem about sum of natural numbers

Following combinatorics problem is claimed to be an open problem in "The Princeton Companion to Mathematics" (pp. 6) Let $a_1,a_2,a_3,...$ be a sequence of positive integers, and suppose that each $...
rationalbeing's user avatar
1 vote
0 answers
274 views

On Primes in Arithmetic Progressions

I was wondering if the following approach is being attempted to prove the twin-prime conjecture. Tao and Green proved in their paper (2006), that there are arbitrarily long arithmetic progressions ...
user136205's user avatar
29 votes
1 answer
3k views

The Riemann zeros and the heat equation

The Riemann xi function $\Xi(x)$ is defined, with $s=1/2+ix$, as $$ \Xi(x)=\frac12 s(s-1)\pi^{-s/2}\Gamma(s/2)\zeta(s)=2\int_0^\infty \Phi(u)\cos(ux) \, du, $$ where $\Phi(u)$ is defined as $$ 2\sum_{...
Stopple's user avatar
  • 11.1k
1 vote
0 answers
112 views

The $p$-adic valuation of powers of consecutive integers

Let $n > 0, K > 0$ integers and, for $i \in \{1,...,n\}$, let $k_i$ and $l_i$ be integers such that $k_i + l_i = K$. Assume that for some $i,j \in \{1,...,n\}$ we have $k_i \neq k_j$. Claim: ...
Daniel W.'s user avatar
  • 365
5 votes
2 answers
862 views

Is every positive integer a sum of at most 4 distinct quarter-squares?

There appears to be no mention in OEIS: Quarter-squares, A002620. Can someone give a proof or reference? Examples: quarter-squares: ${0,1,2,4,6,9,12,16,20,25,30,36,...}$ 2-term sums: ${2+1, 4+1, ...
Clark Kimberling's user avatar
6 votes
3 answers
811 views

Enumerating cosets of the modular group

Suppose we chose the generators $f(z) = z+1, g(z) = z-1, h(z) = -1/z$ for the modular group $\Gamma$ (i.e. the group of fractional linear tranformations $z \mapsto (az +b)/(cz+d)$ with $a,b,c,d \in \...
Pablo Lessa's user avatar
  • 4,304
3 votes
1 answer
277 views

How do modular functions of level $N>1$ transform under the full modular group?

Let $f$ be a modular function of level $N>1$ and let $\gamma\in SL_2(\mathbf Z)$. Write $$f(\gamma\tau)=j(\gamma,\tau)f(\tau).$$ First question What can we say in general about the factor $j(\...
Shimrod's user avatar
  • 2,375
10 votes
5 answers
2k views

The Circle Method and the binary Goldbach Problem

I've been learning about the Circle Method (at the level of the book "An Invitation to Modern Number Theory," by Miller and Takloo-Bighash). The arguments in the book show how the Circle method can ...
Tom Dickens's user avatar
  • 1,077
8 votes
2 answers
2k views

Pair correlation for the Riemann zeros and $(\zeta^\prime(s)/\zeta(s))^\prime$

Added Background: The pair correlation of the zeros of the Riemann zeta function is influenced by the the derivative of the logarithmic derivative $(\zeta^\prime(s)/\zeta(s))^\prime$; see for example ...
Stopple's user avatar
  • 11.1k
0 votes
2 answers
245 views

When the $o$-th division polynomial of an elliptic curve over finite vanishes only at $x$ coordinates?

Need this for probabilistic factoring algorithm. Let $p$ be sufficiently large prime and $E$ the elliptic curve $E /\mathbb{F}_p: y^2=x^3+ax+b$. Let $o=\#E(\mathbb{F}_p)$. $\psi_n$ denote the $n$-...
joro's user avatar
  • 25.4k
1 vote
2 answers
753 views

basis of the lattice generated by the integer points inside a subspace of R^L

Consider $K$ linearly independent vectors $\mathbf{a}_1, \mathbf{a}_2, ..., \mathbf{a}_K \in \mathbb{Z}^L$, where $1 \leq K<L $. Hence, the span of $\lbrace\mathbf{a}_1, \mathbf{a}_2, ..., \mathbf{...
mohsenh01's user avatar
3 votes
1 answer
124 views

Provenance of a result on regular simplices with integer vertices

There are several MO questions related to the question of characterizing those integers $n$ for which there exists a regular $n$-simplex in $\mathbb{R}^n$ with integer vertices, e.g., coordinates of ...
Richard Stanley's user avatar
17 votes
2 answers
3k views

Some unpublished notes of Hofstadter

I'm looking for some unpublished notes called "Eta Lore," which are apparently related to a talk Douglas Hofstadter first gave at the Stanford Math Club in 1963. I know these notes exist because they'...
4 votes
2 answers
470 views

On the natural density of almost perfect numbers

This question is pretty basic, so I apologize in advance if it is unsuitable for MO. If so, please do let me know and I will migrate it over to MSE. Essentially, by work of Kanold, we know that the ...
Jose Arnaldo Bebita's user avatar
10 votes
2 answers
962 views

Surveys of the items of Erdős' "toolbox"

Could you point out some survey papers and monographs that highlight the kernel of tricks, techniques, and tools that Paul Erdős employed the most in his research work (in particular in graph theory, ...
0 votes
1 answer
322 views

On the largest prime factor of $1+n^k$

For every positive integer $n>1$ , let $f(n)$ denote the largest prime factor of $n$. How fast does $f(1+n^k)$ grow with respect to $k$ ? Is it true that $f(1+n^k) > 2k, \forall n >2, \forall ...
user avatar
7 votes
0 answers
291 views

What does it mean for a complex valued function on $G(\mathbb A)$ to be smooth (or smooth of compact support)?

Let $G$ be a linear algebraic group over a number field $k$. Let $\mathbb A$ denote the adeles of $k$, $\mathbb A_f$ the finite adeles, and $k_{\infty} = \prod\limits_{v \mid \infty} k_v$. Here are ...
D_S's user avatar
  • 6,180
8 votes
1 answer
3k views

Where to start reading into p-adic non-abelian Hodge theory?

I'm curious about Faltings' "A $p$-adic Simpson correspondence". Do you know more detailed, introductory, expositions, surveys, texts of seminars on that? Edit: Annette Werner's survey &...
6 votes
2 answers
730 views

Definition of Hecke operators on orthogonal modular forms

In his paper Automorphic forms with singularities on Grassmannians, Borcherds poses Problem 16.5: "Describe how the correspondence in this paper behaves under the action of Hecke operators." Since ...
user avatar
5 votes
1 answer
414 views

Primality test for $2p+1$

In 1750 Euler stated following theorem : Let $p \equiv 3 \pmod 4$ be prime then $2p+1$ is prime iff $2p+1 \mid 2^p-1$ . In 1775 Lagrange gave a proof of the theorem . Recently I have formulated ...
Pedja's user avatar
  • 2,661
14 votes
1 answer
755 views

Generating function of the Thue-Morse sequence

Let $T$ be the generating function of the Thue-Morse sequence; thus, $T(x)=x+x^2+x^4+x^7+\dotsb$. It is known that $T$ satisfies the nice congruence $$ (1+x)^3 T^2(x) + (1+x)^2 T(x) + x \equiv 0 \...
Seva's user avatar
  • 23k
18 votes
2 answers
3k views

References for Artin motives

I find the following description of Artin motives in Wikipedia. Since these seem to be quite related to number theory, I am interested to learn more in that context. I request the experts available in ...
Anweshi's user avatar
  • 7,442
4 votes
4 answers
3k views

Where do Set Theory and Number Theory meet together?

As all know, by absoluteness theorems in Set Theory, most of theorems in number theory are $ZFC$-provable if and only if they are consistent with $ZFC$, it's because of absoluteness of essence of ...
Rahman. M's user avatar
  • 2,381
10 votes
2 answers
870 views

Bound on gcd of two integers

Well this is a problem I was fiddling with. I came up with it but it probably is not original. Suppose $a\in \mathbb{N}$ is not a perfect square. Then show that : $$\text{gcd}(n,\lfloor{n\sqrt{a}}...
shadow10's user avatar
  • 1,090
4 votes
0 answers
252 views

Height pairings of Heegner points of nontrivial conductor

I am studying Gross's and Zagier's proof of the BSD conjecture for elliptic curves of rank $\leq 1.$ Their calculation essentially boils down to the following ingredients: (1.) Finding a suitable ...
The Thin Whistler's user avatar
5 votes
0 answers
2k views

Jacobi's two-square theorem

Jacobi's theorem is: the number of ways of representing $N$ as a sum of two squares is $4(d_1(N)-d_3(N))$ where $d_i(N)$ is the number of divisors of $N$ that are of the form $4k+i$. I was wondering ...
user47804's user avatar
  • 221

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