The groups with central cyclic commutant are considered. The finitely generated groups with infinite central cyclic commutant are completely described.
A system of linear differential equations with constant coefficients is transformed to the linear-diagonal form. Explicit formulas of a nonlinear transformation of the Jordan normal form for the linear differential system ...
The mixed problem for a hyperbolic equation in an unbounded domain with respect to spatial variables is investigated. Conditions that provide the existence and uniqueness of the solution in generalized Lebesgue spaces are ...
We consider the representations of soluble groups of finite rank over a locally finite field. We found some necessary and some sufficient conditions for the existence of the faithful irreducible representations of soluble ...
We prove the theorem on the continuous dependence of a solution to a degenerate system of differential equations on a parameter in the case of non-fulfilment of the condition ''rank-degree''.
We obtain the conditions, which guarantee the existence of a stratifica of the solution of a stochastic Ito parabolic equation with power nonlinearities.