ACTA MATHEMATICA UNIVERSITATIS COMENIANAE


Volume 68 (1999), No. 1


CONTENTS

The Vector Individual Weighted Ergodic Theorem for Bounded Besicovich Sequences
 p. 1   
K. El Berdan
Abstract     Adobe PDF     Compressed Postscript      

Alexandroff Spaces
 p. 17   
F. G. Arenas
Abstract     Adobe PDF     Compressed Postscript      

An Omega Theorem on Differences of Two Squares, II
 p. 27   
M. Kuhleitner
Abstract     Adobe PDF     Compressed Postscript      

Apollonius' Contact Problem in n-Space in View of Enumerative Geometry
 p. 37   
K. Drechsler and U. Sterz
Abstract     Adobe PDF     Compressed Postscript      

A Topological Representation of Polarity Lattices
 p. 49   
G. Hartung, M. Kamara and C. Sacarea
Abstract     Adobe PDF     Compressed Postscript      

Congruence Classes in Regular Varieties
 p. 71   
R. Belohlavek and I. Chajda
Abstract     Adobe PDF     Compressed Postscript      

On Finite Principal Ideal Rings
 p. 77   
J. Cazaran and A. V. Kelarev
Abstract     Adobe PDF     Compressed Postscript      

The Singular Sets of a Complex of Modules
 p. 85   
H. Rahmati and S. Yassemi
Abstract     Adobe PDF     Compressed Postscript      

Strict Refinement for Direct Sums and Graphs
 p. 91   
A. A. Iskander
Abstract     Adobe PDF     Compressed Postscript      

Diameter in Path Graphs
 p. 111   
A. Belan and P. Jurica
Abstract     Adobe PDF     Compressed Postscript      

Closed Walks in Coset Graphs and Vertex-Transitive Non-Cayley Graphs
 p. 127   
R. Kurcz
Abstract     Adobe PDF     Compressed Postscript      

A Picone Type Identity for Second Order Half-Linear Differential Equations
 p. 137   
J. Jaros and T. Kusano
Abstract     Adobe PDF     Compressed Postscript      

Weak Congruence Semidistributivity Laws and Their Conjugates
 p. 153   
G. Czedli
Abstract     Adobe PDF     Compressed Postscript      

Skew Products in the Centralizer of Compact Abelian Group Extensions
 p. 171   
G. R. Goodson
Abstract     Adobe PDF     Compressed Postscript      

A New Class of Analytic Functions Involving Certain Fractional Derivative Operators
 p. 179   
S. Bhatt and R. K. Raina
Abstract     Adobe PDF     Compressed Postscript