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Now showing items 1-10 of 218

#### The fundemantal group of a generalized trigonal curve

(Osaka Daigaku, 2011)

We develop a modification of the Zariski-van Kampen approach for the computation of the fundamental group of a trigonal curve with improper fibers. As an application, we list the deformation families and compute the ...

#### Widom factors

(Springer Netherlands, 2015)

Given a non-polar compact set K,we define the n-th Widom factor W<inf>n</inf>(K) as the ratio of the sup-norm of the n-th Chebyshev polynomial on K to the n-th degree of its logarithmic capacity. By G. Szegő, the sequence ...

#### On generalized principally quasi-Baer modules

(Birkhaeuser Science, 2013)

Let R be an associative ring with identity. A right R–module M is called
generalized principally quasi–Baer if for any m ∈ M, rR(m R) is left s–
unital as an ideal of R and the ring R is said to be right (left) ...

#### Semigroup actions on sets and the burnside ring

(Springer Science, 2018)

In this paper we discuss some enlargements of the category of sets with semigroup
actions and equivariant functions. We show that these enlarged categories possess
two idempotent endofunctors. In the case of groups these ...

#### Very cleanness of generalized matrices

(Springer, 2016-01)

An element a in a ring R is very clean in case there exists an
idempotent e 2 R such that ae = ea and either a e or a + e is
invertible. An element a in a ring R is very J-clean provided that there
exists an idempotent ...

#### Plane sextics with a type e8 singular point

(Tohoku Daigaku Suugaku Kyoshitsu, 2010)

We construct explicit geometric models for and compute the fundamental groups of all plane sextics with simple singularities only and with at least one type E8 singular point. In particular, we discover four new sextics ...

#### The three equivalent forms of completely positive maps on matrices

(Editura Universitatea din Bucuresti, 2010)

Motived by the importance of quantum operations in quantum
information theory, we rigorously present the three equivalent (Stinespring,
Kraus, and Choi) forms of completely positive maps on full C∗-algebras
of matrices, ...

#### Discretization of hyperbolic type Darboux integrable equations preserving integrability

(American Institute of Physics, 2011)

A method of integrable discretization of the Liouville type nonlinear partial differential equations based on integrals is suggested. New examples of the discrete Liouville type models are presented. © 2011 American Institute ...

#### On plane sextics with double singular points

(, 2013)

We compute the fundamental groups of five maximizing sextics with double singular points only; in four cases, the groups are as expected. The approach used would apply to other sextics as well, given their equations.

#### Sums with convolutions of Dirichlet characters to cube-free modulus

(American Mathematical Society, 2011)

We find estimates for short sums of the form Σnm≤X x1 (n)x 2 (m), where x1 and x2 are non-principal Dirichlet characters to modulus q, a cubefree integer, and X can be taken as small as q 1/2+j{cyrillic, ukrainian}. © 2011 ...