24 citations · 98 across the 69 of their papers we have counts for
8 papers · 1 filter
On the Gomori-Hu inequality
E. Petrov, O. Dovgoshey
It was proved by Gomori and Hu in 1961 that for every finite nonempty ultrametric space the following inequality $|\Sp(X)|\leqslant |X|-1$ holds with $\Sp(X)=\{d(x,y):x,y \…
Boundedness of pretangent spaces to general metric spaces
Viktoriia Bilet, Oleksiy Dovgoshey
Let (X,d,p) be a metric space with a metric d and a marked point p. We define the set of w-strongly porous at 0 subsets of [0,\infty) and prove that the distance set {d(x,p): x\in…
Weak similarities of metric and semimetric spaces
Oleksiy Dovgoshey, Evgeniy Petrov
Let (X,dX) and (Y,dY) be semimetric spaces with distance sets D(X) and, respectively, D(Y). A mapping F : X \to Y is a weak similarity if it is surjective and there exists a strict…
Mean value type inequalities for quasinearly subharmonic functions
Oleksiy Dovgoshey, Juhani Riihentaus
The mean value inequality is characteristic for upper semicontinuous functions to be subharmonic. Quasinearly subharmonic functions generalize subharmonic functions. We find the ne…
A kind of local strong one-side porosity
O. Dovgoshey, V. Bilet
We define and study the completely strongly porous at 0 subsets of R^{+}. Several characterizations of these subsets are obtained, among them the description via an universal prope…
On statistical convergence of metric valued sequences
M. Kuchukaslan, U. Deger, O. Dovgoshey
We study the statistical convergence of metric valued sequences and of their subsequences. The interplay between the statistical and usual convergences in metric spaces is also stu…