On the structure of homoethic functions. (Summary).
On the structure of homothetic functions.
On the superstability of the Pexider type trigonometric functional equation.
On the uniqueness of periodic decomposition
Let be arbitrary nonzero real numbers. An -decomposition of a function f:ℝ → ℝ is a sum where is an -periodic function. Such a decomposition is not unique because there are several solutions of the equation with -periodic. We will give solutions of this equation with a certain simple structure (trivial solutions) and study whether there exist other solutions or not. If not, we say that the -decomposition is essentially unique. We characterize those periods for which essential uniqueness...
On transformations of ordinary differential equations
The paper describes the general form of an ordinary differential equation of the order which allows a nontrivial global transformation consisting of the...
On -invariant measures and a functional equation
One-parameter system of functional equations.
Operations between sets in geometry
An investigation is launched into the fundamental characteristics of operations on and between sets, with a focus on compact convex sets and star sets (compact sets star-shaped with respect to the origin) in -dimensional Euclidean space . It is proved that if , with three trivial exceptions, an operation between origin-symmetric compact convex sets is continuous in the Hausdorff metric, covariant, and associative if and only if it is addition for some . It is also demonstrated that if ,...
Orlicz spaces which are Lp-spaces.
Orlicz spaces which are Lp-spaces. (Summary).
Oscillation criteria for second-order delay, difference, and functional equations.
Oscillation of linear functional equations of higher order
The paper contains sufficient conditions under which all solutions of linear functional equations of the higher order are oscillatory.