Expand all Collapse all | Results 1 - 25 of 212 |
1. CMB Online first
Variants of Korselt's Criterion Under sufficiently strong assumptions about the first term in
an arithmetic progression, we prove that for any integer $a$,
there are infinitely many $n\in \mathbb N$ such that for each
prime factor $p|n$, we have $p-a|n-a$. This can be seen as a
generalization of Carmichael numbers, which are integers $n$
such that $p-1|n-1$ for every $p|n$.
Keywords:Carmichael number, pseudoprime, Korselt's Criterion, primes in arithmetic progressions Category:11A51 |
2. CMB Online first
Vanishing of Massey products and Brauer groups Let $p$ be a prime number and $F$ a field containing a root of
unity of order $p$.
We relate recent results on vanishing of triple Massey products
in the mod-$p$ Galois cohomology of $F$,
due to Hopkins, Wickelgren, MinÃ¡Ä, and TÃ¢n, to classical
results in the theory of central simple algebras.
For global fields, we prove a stronger form of the vanishing
property.
Keywords:Galois cohomology, Brauer groups, triple Massey products, global fields Categories:16K50, 11R34, 12G05, 12E30 |
3. CMB Online first
Resultants of Chebyshev Polynomials: The First, Second, Third, and Fourth Kinds We give an explicit formula for the resultant of Chebyshev polynomials of the
first, second, third, and fourth kinds.
We also compute the resultant of modified cyclotomic polynomials.
Keywords:resultant, Chebyshev polynomial, cyclotomic polynomial Categories:11R09, 11R18, 12E10, 33C45 |
4. CMB Online first
A specialisation of the Bump-Friedberg $L$-function We study the restriction of the Bump-Friedberg integrals to affine
lines $\{(s+\alpha,2s),s\in\mathbb{C}\}$.
It has a simple theory, very close to that of the Asai $L$-function.
It is an integral representation of the product
$L(s+\alpha,\pi)L(2s,\Lambda^2,\pi)$ which we denote by $L^{lin}(s,\pi,\alpha)$
for this abstract, when $\pi$ is a cuspidal automorphic
representation of $GL(k,\mathbb{A})$ for
$\mathbb{A}$ the adeles of a number field. When $k$ is even, we show
that for a cuspidal automorphic representation $\pi$,
the partial $L$-function $L^{lin,S}(s,\pi,\alpha)$ has a pole
at $1/2$, if and only if $\pi$ admits a (twisted) global
period, this gives a more direct proof of a
theorem of Jacquet and Friedberg, asserting
that $\pi$ has a twisted global period if and only if $L(\alpha+1/2,\pi)\neq
0$ and $L(1,\Lambda^2,\pi)=\infty$.
When $k$ is odd, the partial $L$-function is holmorphic in a
neighbourhood of $Re(s)\geq 1/2$ when $Re(\alpha)$ is
$\geq 0$.
Keywords:automorphic L functions Categories:11F70, 11F66 |
5. CMB Online first
$L$-functions for Quadratic Characters and Annihilation of Motivic Cohomology Groups Let $n$ be a positive even integer, and let $F$ be a totally real
number field and $L$ be an abelian Galois extension which is totally
real or CM.
Fix a finite set $S$ of primes of $F$ containing the infinite primes
and all those which ramify in
$L$, and let $S_L$ denote the primes of $L$ lying above those in
$S$. Then $\mathcal{O}_L^S$ denotes the ring of $S_L$-integers of $L$.
Suppose that $\psi$ is a quadratic character of the Galois group of
$L$ over $F$. Under the assumption of the motivic Lichtenbaum
conjecture, we obtain a non-trivial annihilator of the motivic
cohomology group
$H_\mathcal{M}^2(\mathcal{O}_L^S,\mathbb{Z}(n))$ from the lead term of the Taylor series for the
$S$-modified Artin $L$-function $L_{L/F}^S(s,\psi)$ at $s=1-n$.
Keywords:motivic cohomology, regulator, Artin L-functions Categories:11R42, 11R70, 14F42, 19F27 |
6. CMB 2014 (vol 58 pp. 115)
Weak Arithmetic Equivalence Inspired by the invariant of a number field given by its zeta
function, we define the notion of weak arithmetic equivalence and show
that under certain ramification hypotheses, this equivalence
determines the local root numbers of the number field. This is
analogous to a result of Rohrlich on the local root numbers of a
rational elliptic curve. Additionally, we prove that for tame
non-totally real number fields, the integral trace form is invariant
under arithmetic equivalence.
Keywords:arithmeticaly equivalent number fields, root numbers Categories:11R04, 11R42 |
7. CMB 2014 (vol 58 pp. 160)
Some Normal Numbers Generated by Arithmetic Functions Let $g \geq 2$. A real number is said to be $g$-normal if its base $g$ expansion contains every finite sequence of digits with the expected limiting frequency. Let $\phi$ denote Euler's totient function, let $\sigma$ be the sum-of-divisors function, and let $\lambda$ be Carmichael's lambda-function. We show that if $f$ is any function formed by composing $\phi$, $\sigma$, or $\lambda$, then the number
\[ 0. f(1) f(2) f(3) \dots \]
obtained by concatenating the base $g$ digits of successive $f$-values is $g$-normal. We also prove the same result if the inputs $1, 2, 3, \dots$ are replaced with the primes $2, 3, 5, \dots$. The proof is an adaptation of a method introduced by Copeland and ErdÅs in 1946 to prove the $10$-normality of $0.235711131719\ldots$.
Keywords:normal number, Euler function, sum-of-divisors function, Carmichael lambda-function, Champernowne's number Categories:11K16, 11A63, 11N25, 11N37 |
8. CMB Online first
Some normal numbers generated by arithmetic functions Let $g \geq 2$. A real number is said to be $g$-normal if its base $g$ expansion contains every finite sequence of digits with the expected limiting frequency. Let $\phi$ denote Euler's totient function, let $\sigma$ be the sum-of-divisors function, and let $\lambda$ be Carmichael's lambda-function. We show that if $f$ is any function formed by composing $\phi$, $\sigma$, or $\lambda$, then the number
\[ 0. f(1) f(2) f(3) \dots \]
obtained by concatenating the base $g$ digits of successive $f$-values is $g$-normal. We also prove the same result if the inputs $1, 2, 3, \dots$ are replaced with the primes $2, 3, 5, \dots$. The proof is an adaptation of a method introduced by Copeland and ErdÅs in 1946 to prove the $10$-normality of $0.235711131719\ldots$.
Keywords:normal number, Euler function, sum-of-divisors function, Carmichael lambda-function, Champernowne's number Categories:11K16, 11A63, 11N25, 11N37 |
9. CMB 2014 (vol 57 pp. 551)
Asymptotic Improvements of Lower Bounds for the Least Common Multiples of Arithmetic Progressions For relatively prime positive integers $u_0$ and $r$, we consider the
least common multiple $L_n:=\mathop{\textrm{lcm}}(u_0,u_1,\dots, u_n)$ of the finite
arithmetic progression $\{u_k:=u_0+kr\}_{k=0}^n$. We derive new lower
bounds on $L_n$ that improve upon those obtained previously when
either $u_0$ or $n$ is large. When $r$ is prime, our best bound is
sharp up to a factor of $n+1$ for $u_0$ properly chosen, and is also
nearly sharp as $n\to\infty$.
Keywords:least common multiple, arithmetic progression Category:11A05 |
10. CMB 2014 (vol 57 pp. 495)
JeÅmanowicz' Conjecture with Congruence Relations. II Let $a,b$ and $c$ be primitive Pythagorean numbers such that
$a^{2}+b^{2}=c^{2}$ with $b$ even.
In this paper, we show that if $b_0 \equiv \epsilon \pmod{a}$
with $\epsilon \in \{\pm1\}$
for certain positive divisors $b_0$ of $b$,
then the Diophantine equation $a^{x}+b^{y}=c^z$ has only the
positive solution $(x,y,z)=(2,2,2)$.
Keywords:exponential Diophantine equations, Pythagorean triples, Pell equations Categories:11D61, 11D09 |
11. CMB 2014 (vol 57 pp. 538)
Infinite Families of $A_4$-Sextic Polynomials In this article we develop a test to determine whether a sextic
polynomial that is irreducible over $\mathbb{Q}$ has Galois group isomorphic
to the alternating group $A_4$. This test does not involve the
computation of resolvents, and we use this test to construct several
infinite families of such polynomials.
Keywords:Galois group, sextic polynomial, inverse Galois theory, irreducible polynomial Categories:12F10, 12F12, 11R32, 11R09 |
12. CMB 2014 (vol 57 pp. 485)
Fourier Coefficients of Vector-valued Modular Forms of Dimension $2$ We prove the following Theorem. Suppose that $F=(f_1, f_2)$ is a $2$-dimensional vector-valued modular form
on $\operatorname{SL}_2(\mathbb{Z})$ whose component functions $f_1, f_2$ have rational Fourier coefficients
with bounded denominators. Then $f_1$ and $f_2$ are classical modular forms on a congruence subgroup of the modular group.
Keywords:vector-valued modular form, modular group, bounded denominators Categories:11F41, 11G99 |
13. CMB 2013 (vol 57 pp. 845)
Factorisation of Two-variable $p$-adic $L$-functions Let $f$ be a modular form which is non-ordinary at $p$. Loeffler has
recently constructed four two-variable $p$-adic $L$-functions
associated to $f$. In the case where $a_p=0$, he showed that, as in
the one-variable case, Pollack's plus and minus splitting applies to
these new objects. In this article, we show that such a splitting can
be generalised to the case where $a_p\ne0$ using Sprung's logarithmic
matrix.
Keywords:modular forms, p-adic L-functions, supersingular primes Categories:11S40, 11S80 |
14. CMB 2013 (vol 57 pp. 877)
On Convolutions of Convex Sets and Related Problems We prove some results concerning covolutions, the
additive energy and sumsets of convex sets and its generalizations. In
particular, we show that if a set $A=\{a_1,\dots,a_n\}_\lt \subseteq
\mathbb R$ has
the property that for every fixed
$1\leqslant d\lt n,$ all differences $a_i-a_{i-d}$, $d\lt i\lt n,$ are distinct, then
$|A+A|\gg |A|^{3/2+c}$ for a constant $c\gt 0.$
Keywords:convex sets, additive energy, sumsets Category:11B99 |
15. CMB 2013 (vol 57 pp. 381)
On Complex Explicit Formulae Connected with the MÃ¶bius Function of an Elliptic Curve We study analytic properties function $m(z, E)$, which is defined on the upper half-plane as an integral from the shifted $L$-function of an elliptic curve. We show that $m(z, E)$ analytically continues to a meromorphic function on the whole complex plane and satisfies certain functional equation. Moreover, we give explicit formula for $m(z, E)$ in the strip $|\Im{z}|\lt 2\pi$.
Keywords:L-function, MÃ¶bius function, explicit formulae, elliptic curve Categories:11M36, 11G40 |
16. CMB 2013 (vol 56 pp. 827)
Erratum to ``Quantum Limits of Eisenstein Series and Scattering States'' This paper provides an erratum to Y. N. Petridis,
N. Raulf, and M. S. Risager, ``Quantum Limits
of Eisenstein Series and Scattering States.'' Canad. Math. Bull., published
online 2012-02-03, http://dx.doi.org/10.4153/CMB-2011-200-2.
Keywords:quantum limits, Eisenstein series, scattering poles Categories:11F72, 8G25, 35P25 |
17. CMB 2013 (vol 56 pp. 673)
Diophantine Approximation for Certain Algebraic Formal Power Series in Positive Characteristic In this paper, we study rational approximations for certain algebraic power series over a finite field.
We obtain results for irrational elements of strictly positive degree
satisfying an equation of the type
\begin{equation}
\alpha=\displaystyle\frac{A\alpha^{q}+B}{C\alpha^{q}}
\end{equation}
where $(A, B, C)\in
(\mathbb{F}_{q}[X])^{2}\times\mathbb{F}_{q}^{\star}[X]$.
In particular,
we will give, under some conditions on the polynomials $A$, $B$
and $C$, well approximated elements satisfying this equation.
Keywords:diophantine approximation, formal power series, continued fraction Categories:11J61, 11J70 |
18. CMB 2012 (vol 57 pp. 105)
On the Counting Function of Elliptic Carmichael Numbers We give an upper bound for the number elliptic Carmichael numbers $n \le x$
that have recently been introduced by J. H. Silverman in the case of an elliptic curve without complex multiplication (non CM). We also discuss
several possible ways for further improvements.
Keywords:elliptic Carmichael numbers, applications of sieve methods Categories:11Y11, 11N36 |
19. CMB 2012 (vol 56 pp. 570)
Conjugacy Classes and Binary Quadratic Forms for the Hecke Groups In this paper we give a lower bound
with respect to block length
for the trace of non-elliptic conjugacy classes
of the Hecke groups.
One consequence of our bound
is that there are finitely many
conjugacy classes of a given trace in any Hecke group.
We show that another consequence of our bound
is that
class numbers are finite for
related hyperbolic \( \mathbb{Z}[\lambda] \)-binary quadratic forms.
We give canonical class representatives
and calculate class numbers
for some classes of hyperbolic \( \mathbb{Z}[\lambda] \)-binary quadratic forms.
Keywords:Hecke groups, conjugacy class, quadratic forms Categories:11F06, 11E16, 11A55 |
20. CMB 2012 (vol 56 pp. 695)
Carmichael meets Chebotarev For any finite Galois extension $K$ of $\mathbb Q$
and any conjugacy class $C$ in $\operatorname {Gal}(K/\mathbb Q)$,
we show that there exist infinitely many Carmichael numbers
composed solely of primes for which the associated class of Frobenius
automorphisms is $C$. This result implies that for every natural
number $n$ there are infinitely many Carmichael numbers of the form
$a^2+nb^2$ with $a,b\in\mathbb Z $.
Keywords:Carmichael numbers, Chebotarev density theorem Categories:11N25, 11R45 |
21. CMB 2012 (vol 56 pp. 785)
Small Prime Solutions to Cubic Diophantine Equations Let $a_1, \cdots, a_9$ be non-zero integers and $n$ any integer. Suppose
that $a_1+\cdots+a_9 \equiv n( \textrm{mod}\,2)$ and $(a_i, a_j)=1$ for $1 \leq i \lt j \leq 9$.
In this paper we prove that (i) if $a_j$ are not all of the same sign, then the above cubic
equation has prime solutions satisfying
$p_j \ll |n|^{1/3}+\textrm{max}\{|a_j|\}^{14+\varepsilon};$
and (ii) if all $a_j$ are positive and $n \gg \textrm{max}\{|a_j|\}^{43+\varepsilon}$, then the cubic
equation $a_1p_1^3+\cdots +a_9p_9^3=n$ is soluble in primes $p_j$.
This result is the extension of the linear and quadratic relative problems.
Keywords:small prime, Waring-Goldbach problem, circle method Categories:11P32, 11P05, 11P55 |
22. CMB 2012 (vol 56 pp. 759)
A Generalization of a Theorem of Boyd and Lawton The Mahler measure of a nonzero $n$-variable polynomial $P$ is the integral of
$\log|P|$ on the unit $n$-torus. A result of Boyd and Lawton says that
the Mahler measure of a multivariate polynomial is the limit of Mahler
measures of univariate polynomials. We prove the analogous
result for different extensions of Mahler measure such as generalized
Mahler measure (integrating the maximum of $\log|P|$ for possibly
different $P$'s),
multiple Mahler measure (involving products of $\log|P|$ for possibly
different $P$'s), and higher Mahler measure (involving $\log^k|P|$).
Keywords:Mahler measure, polynomial Categories:11R06, 11R09 |
23. CMB 2012 (vol 56 pp. 844)
On the Average Number of Square-Free Values of Polynomials We obtain an asymptotic formula for the number
of square-free integers in $N$ consecutive values
of polynomials on average over integral
polynomials of degree at most $k$ and of
height at most $H$, where $H \ge N^{k-1+\varepsilon}$
for some fixed $\varepsilon\gt 0$.
Individual results of this kind for polynomials of degree $k \gt 3$,
due to A. Granville (1998),
are only known under the $ABC$-conjecture.
Keywords:polynomials, square-free numbers Category:11N32 |
24. CMB 2012 (vol 56 pp. 829)
On Mertens' Theorem for Beurling Primes Let $1 \lt p_1 \leq p_2 \leq p_3 \leq \dots$ be an infinite sequence
$\mathcal{P}$ of real numbers for which $p_i \to \infty$, and associate to
this sequence the \emph{Beurling zeta function} $\zeta_{\mathcal{P}}(s):=
\prod_{i=1}^{\infty}(1-p_i^{-s})^{-1}$. Suppose that for some constant
$A\gt 0$, we have
$\zeta_{\mathcal{P}}(s) \sim A/(s-1)$, as $s\downarrow 1$. We prove that
$\mathcal{P}$ satisfies an analogue of a classical theorem of Mertens:
$\prod_{p_i \leq x}(1-1/p_i)^{-1} \sim A \e^{\gamma} \log{x}$, as
$x\to\infty$.
Here $\e = 2.71828\ldots$ is the base of the natural logarithm and
$\gamma = 0.57721\ldots$ is the usual Euler--Mascheroni constant. This
strengthens a recent theorem of Olofsson.
Keywords:Beurling prime, Mertens' theorem, generalized prime, arithmetic semigroup, abstract analytic number theory Categories:11N80, 11N05, 11M45 |
25. CMB 2012 (vol 56 pp. 602)
Resultants of Chebyshev Polynomials: A Short Proof We give a simple proof of the value of the resultant of two Chebyshev polynomials
(of the first or the second kind),
values lately obtained by D. P. Jacobs, M. O. Rayes and V. Trevisan.
Keywords:resultant, Chebyshev polynomials, cyclotomic polynomials Categories:11R09, 11R04 |