Translated from Russian.

Includes bibliographical references.;Bibliography: p.

Properties of some subsystems of classical and intuitionistic propositional calculi /; On a theorem in additive number theory /; On the theory of distribution of primes based on I. M. Vinogradov's method of trigonometric sums /; A simplification of A. Selberg's elementary proof of the asymptotic law of distribution of prime numbers /; On the theory of inverse semigroups and generalized groups /; Lectures on semigroups of transformations /; Irreducible representations of the group U(n) of class I relative to U(n - 1) /; Irreducible representations of the group U(n) of class I relative to U(n - 1) /; Special functions connected with representations of the group U(n) of class I relative to U(n - 1)\ (n\ge 3) /; Irreducible representations of polycyclic groups over an absolute algebraic field of prime characteristic /; On torsion-free groups whose irreducible representations over some field are all finite-dimensional /; Symmetric groupoids / M. I. Semenenko; A. F. Lavrik; A. F. Lavrik; A. G. Postnikov and N. P. Romanov; Boris M. [B. M. Sain] Schein; B. M. [Sain] Schein; R. L. Sapiro; N. Ja. Vilenkin and R. L. Sapiro; R. L. Sapiro; E. M. [Levics] Levic; E. M. [Levics] Levic; A. I. Malcev