Geodesic

Sommaire du Fascicule no. 1

The uniqueness of the element of best mean approximation to a continuous function using splines with fixed nodes
p. 3-14
Order of $(C,\alpha)$-approximations on certain classes of periodic functions
p. 15-20
The V.\,A.~Steklov problem in the theory of orthogonal polynomials
p. 21-32
The approximation of a~H\"older class of two variables by Riesz spherical means
p. 33-43
The three-lines theorem
p. 45-53
Holonomic functions in a~polycircle with nonnegative imaginary part
p. 55-61
Rearrangements of the Haar system
p. 63-71
A~remark concerning Pincherle bases
p. 73-78
Dependence of differential properties of a~function on the speed of its rational approximations in the metrics of $L_p$
p. 79-90
Embedding theorems for fractional norms generated by an elliptic operator
p. 91-100
Interpolation in certain Hilbert spaces of analytic functions
p. 101-112
The problem of generalized Green matrices
p. 113-120
Biharmonic functions, nonnegative in a~half-strip
p. 121-128
The use of a~connection between integral transforms for the computation of integrals
p. 129-137
Modulus of continuity of solutions of second-order elliptic equations on a~plane
p. 139-148
Structure of the point spectrum of a~linear operator
p. 149-158
Discrete groups generated by reflections in the faces of symplicial prisms in Lobachevskian spaces
p. 159-164
Factorization of a~convolution-type operator
p. 165-171
The spectral sequence of a~fibration and the skeletons of the base
p. 173-183

Sommaire du Fascicule no. 2

A~tauberian theorem
p. 187-190
The haar system as an unconditional basis in $L_p[0, 1]$
p. 191-196
Conditions for the representability of analytic functions by series of rational functions
p. 197-203
A~boundary uniqueness theorem for holomorphic functions of several complex variables
p. 205-212
The stability of the completeness and minimality in $L^2$ of a~system of exponential functions
p. 213-219
The connection between the extremality of the coefficients of a~Laurent series and the completeness of a~set of analytic functions in the space of continuous functions
p. 221-228
The representation of entire functions by series in solutions of differential equations
p. 229-234
An example of a~continuous flow on the torus with mixed spectrum
p. 235-240
Determination of the two-class imaginary quadratic fields with an even discriminant by Heegner's method
p. 241-246
Extremal property of some surfaces in $n$-dimensional Euclidean space
p. 247-254
Axiomatic definition of a~quotient ring
p. 255-262
Semivarieties and Schreier varieties of unary algebras
p. 263-270
Sufficient conditions for the self-adjointness of the Sturm--Liouville operator
p. 271-280
Nonsimplicity of the group of unimodular automorphisms of the affine plane
p. 289-293
Ideal points of semisimple Jordan algebras
p. 295-305
Covering elements in the lattice of varieties of algebras
p. 307-312
A~necessary condition for the existence of perfect codes in Lie metric
p. 313-320
The transcendental rank of the formulas of an $\aleph_1$-categorical theory
p. 321-329
Cross products of complete orthonormal systems of functions
p. 331-340
The Fourier coefficients with respect to the Faber--Schauder system
p. 341-352

Sommaire du Fascicule no. 3

Growth of a~mixed derivative of a~function of $C^{(l_1,l_2)}$
p. 355-362
Absolute convergence of Fourier series with respect to bounded systems
p. 363-370
Smoothing by $L$-spline functions of many variables
p. 371-379
Equisummability in the sense of M.~Riesz of expansions in certain systems of exponential functions
p. 381-386
Even diameters of the classes $W^{(r)}H_\omega$ in the space $C_2\pi$
p. 387-392
Summability of series with respect to a~Haar system by the $(C,1)$ method
p. 393-404
Order function for almost all numbers
p. 405-414
Noncommutative cohomologies and Mumford groups
p. 415-419
An upper bound for the $\alpha$-height of $(0,1)$-matrices
p. 421-429
Smoothness of functions with respect to a~set
p. 431-436
Uniqueness of the solution of a~second-order hyperbolic equation in a~normal cylinder
p. 437-444
A~remark concerning the theory of scattering for a~perturbed polyharmonic operator
p. 445-454
Expansion in characteristic functions of the Schr\"odinger operator with a~singular potential
p. 455-465
Peano's theorem in an infinite-dimensional Hilbert space is false even in a~weakened formulation
p. 467-477
Mean value theorem and a~maximum principle for Kolmogorov's equation
p. 479-489
Bicompact extensions with the first axiom of countability and continuous mappings
p. 491-499
Number of equivalence classes of weakly equivalent lattices
p. 501-508
Complete extensions of topological spaces
p. 509-513

Sommaire du Fascicule no. 4

Singularities of carleman type for subsystems of a~trigonometric system
p. 515-520
Sequences of closed sets of bounded variation converging in the deviation metric
p. 521-526
Fourier sums for the Banach indicatrix
p. 527-532
The approximation of Сauchy singular integrals and their limiting values at the endpoints of the curve of integration
p. 533-542
The divergence of the image of a~point sequence under a~conformal mapping
p. 543-550
A~method of constructing generalized difference sets
p. 551-560
Algebraic curves over functional fields with a~finite field of constants
p. 561-570
A~case of the generation of a~periodic motion with homoclinic curves
p. 571-580
Nonlocal solvability of the Cauchy problem for second-order nonlinear parabolic equations
p. 581-586
Hilbert boundary-value problem for a~class of singular matrix-functions
p. 587-594
Methods of solving Fredholm equations optimal on classes of functions
p. 595-602
Transformations in hypercomplex Riemannian spaces
p. 603-612
Asymptotic behavior of the dwell time distribution for a~random walk on a~positive semi-axis
p. 613-620
Existence theorems for a~semi-Markov process with an arbitrary set of states
p. 621-630
The number of self-dual types in finite-valued logics
p. 631-639
Random hypertrees and hyperforests
p. 641-650
The Mathieu group $M_{12}$
p. 651-660
Algebraic independence of some values of the exponential function
p. 661-672
Salem Prize awarded to E.\,M.~Nikishin

Sommaire du Fascicule no. 5

250-year jubilee of the Academy of Sciences of the USSR
p. 677-678
On a~relationship in the theory of Fourier series
p. 679-682
On the analytic continuation of functions defined by regrouped power series
p. 683-690
The argument principle and integral curvature of minimal surfaces
p. 691-700
Convexity and star-shapedness of the level curves of polynomials
p. 701-710
On the logarithmic derivative of a~meromorphic function
p. 711-718
Projection constants of symmetric spaces
p. 719-727
On uniqueness of the polynomial of best approximation of the function $\cos kx$ by trigonometric polynomials in the $L$ metric
p. 729-737
Generalization of the Martinelli--Bochner integral representation
p. 739-747
On the error made in recovering functions of a~certain class on parallelepiped-type grids
p. 749-756
On a~problem in the theory of rings of principal ideals
p. 757-763
On localization of the characteristic numbers of real matrices
p. 765-768
On the number of steiner triple systems
p. 769-774
Calculus of ordered operators on a~factor algebra
p. 775-786
Solvability of a~convolution equation in convex domains
p. 787-796
On the modulus of continuity of an operator of best approximation
p. 797-808
Duality between differentiability and rotundity for convex functions
p. 809-820
Approximation of continuous periodic functions of many variables by spherical Riesz means
p. 821-832
Letter to the editor

Sommaire du Fascicule no. 6

On sufficient conditions for the convergence of double series over rectangles
p. 835-838
Normal functions possessing angular boundary values almost everywhere
p. 839-846
On two basic conditions for the asymptotic representation of polynomials orthonormal on the unit circle
p. 847-855
On the zeros of analytic functions belonging to Gevrey classes
p. 857-863
On a~classification of meromorphic functions defined in the finite plane
p. 865-874
Kripke semantics for modal systems including S4.3
p. 875-884
Some properties of a~regular solution of the Helmholtz equation in a~two-dimensional domain
p. 885-890
On local uniqueness of the solution of boundary-value problems
p. 891-895
On a~Kneser-type problem for a~system of ordinary differential equations
p. 897-906
On a~class of nonlinear problems on characteristic values
p. 907-913
On the characteristic of sets in the space conjugate to a~normed structure
p. 915-924
A~general theorem concerning semi-groups with certain finiteness conditions
p. 925-935
On the synthesis of self-correcting schemes from functional elements with a~small number of reliable elements
p. 937-944
On generalized resolvents and spectral functions of differential operators of even order in a~space of vector-valued functions
p. 945-954
Approximation of certain classes of differentiable periodic functions by interpolational splines in a~uniform decomposition
p. 955-966
On Riesz's interpolational formula and Bernshtein's inequality for functions on homogeneous spaces
p. 967-978