Kagan, D. Z.
Published in
Lobachevskii Journal of Mathematics

In this paper questions of the existence of non-trivial pseudocharacters for different classes of groups and the most important applications of pseudocharacters are considered. We review the results obtained for non-trivial pseudocharacters of free group constructions. Pseudocharacter is the real functions f on a group G such that 1) |f(ab) − f(a) ...

Bikchantaev, I. A.
Published in
Lobachevskii Journal of Mathematics

We consider a periodic problem of conjugation on the real axis for a linear differential elliptic equation of second order with constant coefficients. There is known a representation of general solution of the equation in terms of analytic functions depending on affine connected variables. We introduce auxiliary analytic functions enabling us to re...

Datt, Gopal Chugh, Renu Jakhar, Jagjeet
Published in
Lobachevskii Journal of Mathematics

In this paper, conditions are derived for the multiplication, composition and weighted composition operators on weighted Lorentz–Karamata–Bochner (WLKB) spaces Lp,q,w;b, 1

Sheina, K. I. Zhukova, N. I.
Published in
Lobachevskii Journal of Mathematics

For a complete Cartan foliation (M,F) we introduce two algebraic invariants g0(M,F) and g1(M,F) which we call structure Lie algebras. If the transverse Cartan geometry of (M,F) is effective then g0(M,F) = g1(M,F). Weprove that if g0(M,F) is zero then in the category of Cartan foliations the group of all basic automorphisms of the foliation (M,F) ad...

Safarov, D. S. Shodiev, M. S.
Published in
Lobachevskii Journal of Mathematics

The problem of the existence of twice periodic solutions of a nonlinear elliptic system of second-order equations on a plane whose main periods are given is studied. Conditions for the existence of solutions with prescribed poles, as well as with prescribed zeros and poles, are obtained.

Eskandarian, Zohreh
Published in
Lobachevskii Journal of Mathematics

We consider linear normed spaces of measurable functions dominated by positive measurable function powered by real positive parameter. Also, we consider its dual and predual, and we propose a method for constructing a limit spaces of these functional spaces taken by power parameter. We prove that these limit spaces are (LF)-spaces and also prove th...

Bor, Hüseyin
Published in
Lobachevskii Journal of Mathematics

We generalize a known result dealing with absolute Riesz summability factors of infinite series by using a wider class of power increasing sequences. Some new and known results are also obtained.

Krasniqi, Xhevat Z.
Published in
Lobachevskii Journal of Mathematics

We show that the new complex modified trigonometric sums, introduced by others, converge in the space L under a new class of sequences.

Krepkogorskiĭ, V. L.
Published in
Lobachevskii Journal of Mathematics

We consider the space obtained from spaces Triebel–Lizorkin with help interpolation by the real method. Embedding theorems for these spaces are studied. It is shown that the space of traces belong to the same class of spaces.

Barmenkov, A. N. Barmenkov, N. A.
Published in
Lobachevskii Journal of Mathematics

We present an algorithm for construction complete, orthogonal sequences special kind. This systems of functions depend on parameter and may be used for modeling of physical processes.