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Link between integral points on varieties and solutions to Diophantine equations

Let $k$ be a number field, $S$ a finite set of places of $k$ including the infinite ones and $F(X_1,\dots,X_n)$ a polynomial in $k[X_1,\dots,X_n]$. I am looking for notes, books or surveys detailing ...
Wesley Barnard's user avatar
2 votes
0 answers
245 views

Help for reference of moduli stack of fake elliptic curves

I see everywhere the following: Let $B$ be an indefinite quaternion algebra over $\mathbb{Q}$ of discriminant $D$, $\mathcal{O}_B$ be a maximal order, $N$ be an positive integer coprime to $D$. ...
user78140's user avatar
7 votes
1 answer
644 views

(Finite) Models of two subtheories of Peano Arithmetic

Consider first-order theory (with identity) of Peano Artithmetic built in the language $\{S,+,\times,0\}$ and with the following set of axioms: \begin{align} \neg Sx&=0\tag{1}\\\ Sx=Sy&\...
Rafał Gruszczyński's user avatar
5 votes
1 answer
455 views

Large gaps between P2s

Gaps between consecutive primes are $O(n^{\theta+\varepsilon})$ for $\theta=0.525$ and any $\varepsilon>0.$ I was wondering if a better result is known for gaps between numbers with at most two ...
Charles's user avatar
  • 9,114
5 votes
0 answers
359 views

Examples of Rankin-Selberg L-functions from Eisenstein series

I've been digging for awhile to not much success, so I figure I would try here: I am looking for some references which compute explicitly examples of Rankin-Selberg L-functions from the constant ...
Tian An's user avatar
  • 3,799
9 votes
4 answers
1k views

cohomology of moduli spaces

Does anyone know if there's any reference on the $\ell$-adic cohomology of some simple moduli spaces/Shimura varieties, like Siegel moduli varieties $A_{g,N}$ of genus $g$ and level $N,$ for small $g$ ...
shenghao's user avatar
  • 4,265
6 votes
2 answers
861 views

Number of integers coprime to l

A long time ago I've seen a paper considering, given $\ell$ fixed, estimates for $$ \sum_{n \leq x, (n, \ell) = 1} 1 $$ Of course, this is easy to estimate with a trivial error term of $O(\varphi(l))...
kolik's user avatar
  • 293
6 votes
1 answer
192 views

Monte-Carlo computation of the Smith normal form

Quite some time ago I saw an article where a Monte-Carlo algorithm for computing the Smith normal form of an integer matrix was described. In this article the following problem was posed: Suppose $P, ...
Jan-Christoph Schlage-Puchta's user avatar
6 votes
0 answers
332 views

Criteria for irreducibility using the location of complex roots

I would like to see criteria for the irreducibility of a polynomial over $\mathbb{Z}$ based (mainly) on the location of the roots of the polynomial in the complex plane. An example of such a criterion ...
Pablo's user avatar
  • 11.3k
7 votes
2 answers
2k views

Tamagawa Number of Elliptic Curves over $\mathbb{Q}$

I am currently reading a paper by De Weger and one theorem in it proves a bound for the Tamagawa number of any elliptic curve defined over $\mathbb{Q}$. I was wondering if anyone has any good ...
Eugene's user avatar
  • 1,458
2 votes
0 answers
104 views

A question on exponential increasing sequences of natural numbers

Let $(a_i)$ be an exponential increasing sequences of natural numbers; there are constants $a\in(1,2)$, $b>0$ such that $|a_{i}-ba^i|$ is exponentially decreasing. Let $(s_{k})$ be a sequences in $\...
Jörg Neunhäuserer's user avatar
1 vote
1 answer
231 views

If $q^k n^2$ is an odd perfect number with Euler prime $q$, are the following statements known to hold in general? [closed]

(Note: This has been cross-posted to MSE. However, I feel that it is more likely to receive a good answer here, because I believe that it is a research-level question. For the mathematicians who ...
Jose Arnaldo Bebita's user avatar
13 votes
2 answers
880 views

Arithmetic progressions modulo $p$ under the squaring map

I feel that the following problem should be known, but I'm not sure where to look for it. Fix a real constant $\frac{1}{2} \ge \epsilon > 0$. For varying primes $p$, Let $A_p$ denote the set of ...
user avatar
16 votes
0 answers
11k views

Deligne's letter to Jean-Pierre Serre

I'm looking for another letter of Pierre Deligne, this time to Jean-Pierre Serre (from around 1974 I think), in which he proves that the Galois representation associated to a certain Hecke eigenform ...
Przemyslaw Chojecki's user avatar
6 votes
1 answer
497 views

Half integral weight Hecke operators

I would like to find a source giving the exact formula for the product of two Hecke operators $T_{\kappa}(n^2)$ and $T_\kappa(m^2)$ of half integral weight. That is, $\kappa \in \frac 12 \mathbb{Z} - \...
Eren Mehmet Kiral's user avatar
2 votes
0 answers
487 views

On Descartes / spoof odd perfect numbers

Descartes, Frenicle, and subsequently Sorli, conjectured that $k = 1$, if $N = {q^k}{n^2}$ is an odd perfect number given in Eulerian form (i.e., $q$ is prime with $q \equiv k \equiv 1 \pmod 4$ and $\...
Jose Arnaldo Bebita's user avatar
17 votes
1 answer
1k views

Serre and Tate's conjectures on étale cohomology

In the appendix of Serre and Tate "Good Reduction of Abelian Varieties" [Annals of Mathematics 88 (1968), 492-517], the authors make the following conjectures. Suppose that $X$ is a smooth proper ...
Eric Larson's user avatar
  • 1,832
2 votes
0 answers
564 views

Sets of coprime numbers

Consider the set $\{0, 3, 7, 15\}$ of four integers. If you add each of these numbers to a fixed power of 2, then the resulting four numbers are pairwise coprime. For example, $\{4, 7, 11, 19\}$ are ...
user304582's user avatar
7 votes
1 answer
313 views

Prescribed values for the uniform density

Strauch & Tóth [1] Georges Grekos [3][4] showed that for any choice of upper and lower density, there is some subset of $\mathbb{N}$ with the chosen densities, provided the lower is no more than ...
Charles's user avatar
  • 9,114
2 votes
1 answer
364 views

A question on the bounds of the $n$-th composite $c_n$

While trying to prove the inequality $$c_{p_n-m}+c_{m-n}>p_n+2$$ I tried the bounds of $c_n$ (denotes the $n$-th composite number) given in this paper to prove that the sum $c_{p_n-m}+c_{m-n}$ ...
user avatar
3 votes
0 answers
97 views

A sieve result with two parameters

I proved the following sieve result and - since the proof is quite long and I need to use it in a work - I am looking for a reference to it (or at least something from which it could be proved quickly)...
user avatar
2 votes
0 answers
149 views

$f(x)$-th largest number of prime factors

Given a sufficiently well-behaved function $1\le f(x)\le x$ and a multiset $S=\{\omega(n): 1\le n\le x\}$, what can be said about the asymptotics of the $f(x)$-th largest member of $S$? In other words,...
Charles's user avatar
  • 9,114
5 votes
2 answers
1k views

Survey of Algebraic K-Theory Since 1980?

I just came across Charles Weibel's Development of Algebraic K-Theory until 1980, and found it really helpful. Is there been anything analogous which surveys the developments in the last 30 years? I'...
Jesse Wolfson's user avatar
2 votes
2 answers
334 views

What should I read if I want to learn about integral structures on classical algebraic groups?

I'm looking to learn about integral structures (or models?) on classical algebraic groups. To begin with I have been learning about algebraic groups, quadratic forms and lattices. And also looking at ...
Chris Birkbeck's user avatar
0 votes
1 answer
1k views

Name of a conjecture on difference of prime numbers? [closed]

Hello Dear there is a conjecture for which I do not know how it is called. The conjecture is: Every even number can be always written as the difference between two prime numbers. Could you please ...
ali's user avatar
  • 3
3 votes
0 answers
220 views

Almost primes in short intervals

Define an integer $n$ to be a $k$-almost prime if it has at most $k$ distinct primes factors. A detecting function for the set of such numbers is the generalized von Mangoldt function given by $\...
Dead-End's user avatar
  • 141
2 votes
1 answer
223 views

Level-Lowering in Weight 2

Let $N$ and $p$ be relatively prime integers with $p$ a prime. Suppose $f$ is a weight $k=2$ (normalized, cuspidal, etc) newform of level $\Gamma_1(N) \cap \Gamma_0(p)$. I seem to recall the existence ...
Jeff H's user avatar
  • 1,422
2 votes
1 answer
208 views

Enumerating positive fractions (reference missing)

I remember that the recursion $r(0)=0, \ \ r(n+1)=\frac{1}{2 [r(n)]+1-r(n)}$ produces a sequence of rational values $ 0 \mapsto 1 \mapsto 1/2 \mapsto 2 \mapsto 1/3 \mapsto ... $ which exausts the ...
ccarminat's user avatar
  • 373
4 votes
1 answer
590 views

To which automorphic forms/rep's over a function field can we associate a Galois representation?

As far as I understand it, by the work of Lafforgue (cf. Laumon, "Cohom. of Drinfeld ... II", Thm 12.4.1) there is a Galois representation associated to an irreducible cuspidal automorphic ...
anonymous's user avatar
12 votes
3 answers
881 views

What does the computer suggest about the parity of p(n), for n in a fixed arithmetic progression?

Let p(n) be the number of partitions of n. A famous theorem of Euler allows one to compute the parity of p(n) quickly for quite large n. In: On the distribution of parity in the partition function, ...
paul Monsky's user avatar
  • 5,422
3 votes
1 answer
246 views

Numbers with balanced diophantine approximations

This is a follow-up to Question 146635, namely Expected symmetry in the diophantine approximations of an irrational number, which I will refer to for notation and terminology used here without ...
Salvo Tringali's user avatar
1 vote
0 answers
87 views

Diophantine equation $z=(ax+by+c)/(dxy)$, references? [closed]

I am looking for some sources (books or papers) which discuss the Diophantine equation $$ z=\frac{ax+by+c}{dxy} $$ where $a,b,c,d$ are given positive integers. Could anyone give some references? ...
asad's user avatar
  • 841
4 votes
3 answers
1k views

Companion forms

What is the best known result concerning the existence of companion forms for classical modular forms? Gross' tameness criterion paper is always mentioned with a "unchecked compatibility" caveat? ...
akula's user avatar
  • 173
16 votes
1 answer
2k views

Reference for the `standard' Tate curve argument.

I'd like a reference (e.g. something published somewhere that I can cite in a paper) for the proof of the following: Let $E$ be an elliptic curve over $\mathbb Q$ with minimal discriminant $\Delta$...
David Zureick-Brown's user avatar
-1 votes
1 answer
376 views

Collatz property implying infinite "fall below" trajectories, is it known?

(this was discovered analyzing Collatz empirically.) a key aspect of resolving Collatz involves looking at the number of iterations for trajectories to "fall below" the initial value. consider a ...
vzn's user avatar
  • 529
-2 votes
1 answer
1k views

Why should I believe in the Siegel's and Hasse's rationale ?

Hello everyone, I was deeply attracted by the Hasse and Siegel's theorems while studying $p$-adic analysis. While reading a paper B.J. Birch and H.P.F. Swinnerton-Dyer - Notes on elliptic curves. I, ...
Shanmukha_Srinivasan's user avatar
3 votes
1 answer
303 views

Higher dimensional analogue of Thue's equation

The classical Thue equation is $$\displaystyle F(x,y) = h,$$ for a binary form $F(x,y) \in \mathbb{Z}[x,y]$. Recall that a binary form is a polynomial in two variables which is homogeneous, and $h$ ...
Stanley Yao Xiao's user avatar
2 votes
3 answers
912 views

Reference on generators of subgroups of symplectic groups

We should start with the definition of the symplectic group for an arbitrary ring $R$. The symplectic group $Sp(g,R)$ is the subgroup of $SL(2g,R)$ such that all elements satisfy $M=J_g^t M J_g$ with $...
Tom's user avatar
  • 85
11 votes
0 answers
282 views

Reference request: a combinatoric result [closed]

When I tried to construct a counterexample in my research, I encountered the following result, which should be true. Let $m=m(n)$ be a function that grows faster than $\sqrt n$, so $m(n) = \omega(\...
Zhu Cao's user avatar
  • 211
7 votes
1 answer
288 views

Expected symmetry in the diophantine approximations of an irrational number

Given $x \in \mathbb{R}$ we will write $\{x\}$ for the fractional part of $x$ and $\|x\|$ for the distance of $x$ from the nearest integer, in such a way that $\{x\} = x - \lfloor x \rfloor$ and $\|x\|...
Salvo Tringali's user avatar
3 votes
1 answer
562 views

Volume of PGL(2,F) \ PGL(2, A)

Let $F$ be a global field. What is the measure of $PGL_2(F) \backslash PGL_2(\mathbb{A})$? This depends of course on the normalizations of the Haar measures on $PGL_2(F)$ and $PGL_2(\mathbb{A})$. ...
Marc Palm's user avatar
  • 11.2k
1 vote
1 answer
122 views

Source for equations involving congruences of Fibonacci and Lucas numbers

In a paper of Cohn (see here), he uses some formulae involving congruences of Lucas- and Fibonacci-numbers (equations 11,12,13 in the preliminaries section). Does anyone know a source for these (and ...
Martin's user avatar
  • 1,101
5 votes
0 answers
143 views

Reference request: "effective'' semistable reduction

I am looking for the origin of the following idea: suppose $m$ and $n$ are relatively prime integers $\geq 3$. Let $E$ be an elliptic curve over a number field $K$. Let $L/K$ be a finite extension ...
TVA's user avatar
  • 51
5 votes
1 answer
2k views

Galois representation associated to a modular form is crystalline iff...

I am looking for the reference for the following fact (used, for example, in the proof of theorem 4.4. in Breuil's expose about local-global compatibility at Bourbaki): For $f$ a modular cuspidal ...
Przemyslaw Chojecki's user avatar
6 votes
0 answers
380 views

Large sets not containing arithmetic progressions of length 3 in intervals

Given a large enough natural number $N$, let $\Delta_N=\{A \subseteq [N, 2N]: A$ contains no arithmetic progressions of length $3 \},$ where for natural numbers $N<M$ we have $[N, M]=\{N, N+1, ..., ...
Mohammad Golshani's user avatar
3 votes
0 answers
181 views

Factorization of linear recurrences

For each (commutative unitary) ring $R$, let $\mathfrak{R}(R)$ be the set of all linear recurrences over $R$, that is, the set of all sequences $(a(n))_{n \geq 0}$ in $R$ such that $$a(n+k) = r_1 a(n+...
user avatar
2 votes
1 answer
264 views

The number of different lattice triangles

Two convex lattice polygons are equivalent if there is a lattice-preserving affine transformation mapping one of them to the other. Equivalent polygons have the same area. Let $H(A)$ denote the number ...
Alexey Ustinov's user avatar
7 votes
1 answer
653 views

Closed form for derivatives $\zeta^{(n)}(1/2)$

According to mathworld 41,42. "Derivatives $\zeta^{(n)}(1/2)$ can also be given in closed form" with example for the first derivative. What is the closed form? References? The motivation is that ...
joro's user avatar
  • 25.4k
5 votes
0 answers
522 views

Moduli interpretation of Hecke operators on Shimura curves

In his book on Automorphic Forms, Shimura gives (chapter 9) definitions of the the Hecke operators for Shimura curves. One can give definitions of the Hecke and Atkin-Lehner operators in terms of the ...
LMN's user avatar
  • 3,555
1 vote
0 answers
262 views

$\mathfrak{q}$-ideal class bound

Let $K$ be a number field, $\mathcal{O}_K$ be its ring of integers. Let $\mathfrak{q}$ be a nonzero ideal in $\mathcal{O}_K$. The $\mathfrak{q}$-ideal class group consists of equivalence classes of ...
Sungjin Kim's user avatar
  • 3,320

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