Differentiation of fractional order onp-groups,approximation properties

G- p- . [5] - (G) L _r(G) (1r<), . . , - . , , , . . , X. , . (. [1], [2] [4]).     

Onp-Helson sets in R n

p- . E R ⁿ -, f () _p(R ⁿ)., ER ⁿ 2nq ₀, E— - q ₀(q ₀-1). : q₀>2 n1 E R ⁿ 2nq ₀, p- p<₀. , f-[-, ]ⁿ, f A _p(R ⁿ) , _p([-, ]ⁿ) (1 << ).     

Fortsetzungssätze und Moduln über Semifields

. . — . — —.

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Herrn Professor Dr. Frank Terpe zum 60. Geburtstag gewidmet     

Sets of uniqueness and closed subgroups in Vilenkin groups

, ( ) . , : , , .

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This research was partially supported by National Science Foundation under grant INT-8400708.     

Sharp Nikolskii inequalities with exponential weights

w _a(x)=exp(–x^a), xR, a0. , N _n (a,p,q) — (2), _n P _nw_ap, CN_n(a,p, q)P_nw_aq. , — , {P _n}, .

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This material is based upon research supported by the National Science Foundation under Grant No. DMS-84-19525, by the United States Information Agency under Senior Research Fulbright Grant No. 85-41612, and by the Hungarian Ministry of Education (first author). The work was started while the second author visited The Ohio State University between 1983 and 1985, and it was completed during the first author's visit to Hungary in 1985.     

On a class of orthogonal series

, [0, 1], (n+1) n-. . [2]. — (. 5.4 5.6). . 6.4 2 [5]. , [4]. , , [6] [7]. [1].     

On the degree of weighted polynomial approximation of holomorphic functions

[4] , —. , , , [2] [7].     

On the limit superior of analytic sets

. , A ₀,A ₁,— - lim supA _j - H, . , - - . , , ; , , . - . - .     

On the convergence of Fourier series in the metric ofL 1

L ¹ .      

Integrability of multiple Walsh series and Parseval's formula

f(x,y) _jk . , {c _jk} , f(x, )(, ) [0,1)&#x0445;[0,1) , - (0,0). , , f, - f. , , , [1] . . - [5] [6].

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This research is supported by National Science Council, Taipei, R.O.C. under Grant #NSC 84-2121-M-007-026.     

Pointwise convergence of multiple Fourier series using different convergence notions

, . , L ^p (²) p>1 . , C(T³), - , . - .

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This work was completed while the first named author was a visiting professor at Indiana University, Bloomington, Indiana; and the second named author was a visiting professor at Ohio State University, Columbus, Ohio, U.S.A.     

Central limit theorems for Walsh series with general gaps

. [1]. 3 - .     

Arithmetic properties of the Markov function for the Jacobi weight

. . .     

On summability of subsequences of partial sums of trigonometric Fourier series

n- (n1) fL ^p ([–, ] ⁿ ),=1 = (L C) . , , f([–, ] ⁿ ).     

On certain imbedding and extension theorems for a weighted class of functions

n- , S n–1 m (0m<n), () S . () , ().     

О граничном поведени и неограниченных супергармонических функций

In this paper it is proved that a function, superharmonic on a domain inR ⁿ⁺¹ with Lipschitz boundary, cannot have nontangential limit equal to + on a set of positiven-dimensional measure on the boundary. As a corollary, a generalization of the uniqueness theorem of Lusin-Privalov on the nontangential limits of functions, analytic on a domain in the complex plane, is obtained for the case of functions, analytic on a domain in C ⁿ (n>1) with Lipschitz boundary. Formulation of a generalization of the main theorem is also given for the case of the solutions of uniformly elliptic equations with infinitely smooth coefficients.

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Moduli of smoothness and best approximation in the spacesL p , 0<p<1

L ^p , 0<<1, .     

On the solution of a generalized Schrödinger-type equation

Lu(t)+(u,F)g(t)=f(t), tS. , ( F, g). .

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The authors wish to thank Professor Yu. A. Rozanov for his help and discussions.     

On shifts of sequences

X ₂ ={x _k } _k=2 X={x _k } _k=1 . , , ( , ) . , , X— , , X ₂ H, , , , , X ₂ H.