3 papers
math.OC2025
Two characterizations of quasiconvexity
WÅodzimierz Fechner
We present two characterizations of quasiconvexity for radially semicontinuous mappings defined on a convex subset of a real linear space. As an application we obtain an extension…
math.CA2024
On a generalized conjecture by Alzer and Matkowski
WÅodzimierz Fechner, Marta PierzchaÅka, Gabriela Smejda
We study a recent conjecture proposed by Horst Alzer and Janusz Matkowski concerning a bilinearity property of the Cauchy exponential difference for real-to-real functions. The ori…
math.CA2024
Characterizations of second-order differential operators
WÅodzimierz Fechner, Eszter Gselmann, Aleksandra ÅwiÄ tczak
{Let be positive integers with , and be a domain.} By the well-known properties of the Laplacian and the gradient, we have \[ Î(f\cdot g…