Contents

Russian Mathematics

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Vol. 66, No. 2, 2022

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On the Keldysh Problem for a Mixed-Type Equation with Two Singular Lines

A. A. Abashkin p. 1  abstract

On Some Aspects of the Kegel–Wielandt σ-Conjecture

S. F. Kamornikov and V. N. Tyutyanov p. 15  abstract

A Study of a Posteriori Stopping in Iteratively Regularized Gauss–Newton-Type Methods for Approximating Quasi-Solutions of Irregular Operator Equations

M. M. Kokurin p. 24  abstract

Inequalities Refining Relations between Mixed Moduli of Smoothness in L₁ and L_q Metrics

M. K. Potapov and B. V. Simonov p. 36  abstract

Conditional Correctness of the Initial-Boundary Value Problem for a System of High-Order Mixed-Type Equations

K. S. Fayazov and I. O. Khajiev p. 53  abstract

On One Class of Local Groups and Their Representations

S. A. Grigoryan and A. Yu. Kuznetsova p. 64  abstract

A New Primality Test for Natural Integers

Sh. T. Ishmukhametov, R. G. Rubtsova and R. R. Khusnutdinov p. 70  abstract

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