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Asgarov S. (Azerbaijan), Alakbarov M. (Azerbaijan), Aliev Z. (Azerbaijan), Babayev N. (Uzbekistan), Chiladze G. (Georgia), Datskovsky I. (Israel), Garbuz I. (Moldova), Gleizer S. (Germany), Ershina A. (Kazakhstan), Kobzev D. (Switzerland), Kohl O. (Germany), Ktshanyan M. (Armenia), Lande D. (Ukraine), Ledvanov M. (Russia), Makats V. (Ukraine), Miletic L. (Serbia), Moskovkin V. (Ukraine), Murzagaliyeva A. (Kazakhstan), Novikov A. (Ukraine), Rahimov R. (Uzbekistan), Romanchuk A. (Ukraine), Shamshiev B. (Kyrgyzstan), Usheva M. (Bulgaria), Vasileva M. (Bulgar).
1.Introduction. Classes . Let be weighted Hardy space of all functions of complex variable , which are analytic in a circle of , and for which
and
Here is fixed function from the class of measurable on and -periodic functions.
It is said that any function from this class belongs to weight space , if
, .
The case of Lebesque spaces we have for ; in particular, . Denote
,
where is arbitrary interval, and multiplier is equal for by definition. It is said that -condition of Muckenhoupt ([1]) is satisfied and apply the notation , if ,. In the present work, as well as in [1], we suppose . Under this agreement it can suppose that everyone is a function from Hardy class H (the case of [2], p.431), and if , then .
Exclude from consideration a trivial case of . Then . Let E be a set which is measurable by Lebesque. Introduce now the following measure of Е : .
Let be conjugate function; this function exists ([2], p.402) almost everywhere for .
2. Exponential means of power series and Fourier series (conjugate series). Let and {, be a sequence of its Fourier coefficients. In various questions of the analysis (see [3]) arises a problem of behavior of the families means of Fourier series
, , (2.1)
and conjugate Fourier series
, (2.2)
at .
Consider now . The behavior of
=, (2.3)
on boundary of the circle of convergence (), has been well studied. So [2, p.432], exists almost everywhere. Here and the coefficients in the expansion (2.3) can be estimated as
, ;
it is natural to assume that when If we put
~, (2.4)
then (2.3) can be considered as a family of Poisson-Abel means of series (2.4) on boundary of the circle of convergence. Then it will be natural to consider a more general exponential means
, (2.5)
of series (2.4); the case (2.3) we have for . The following statement establishes a relation between classes (), (), () of the families (2.1), (2.2), (2.5).
Тheorem 2.1. If and , then the representation
()= ())
holds. In particular (see (2.3)), =+.
3. The estimates of maximal operators generated by exponential summation methods. Let
. (2.6) Тheorem 3.1. If , then the estimates
;
,
hold for every . Here are constants, which may depend only on indicated indexes.
This result follows from theorem 3.1 and weighted norm inequalities for maximal operator of the type (2.6), generated by the families of (2.1), (2.2); these inequalities in the special case of see in [3].
4. Result of convergence.
Theorem 4.1. Suppose that . Then the relation = holds -almost everywhere for each and in metric , , for any .
The result follows from the theorem 4.1 and relations = , =, which hold -almost everywhere for each and in metrics ,, for any
2. Zygmund A. Trigonometric series. Vol. 1. Moscow: “Mir”, 1965. –615 p.
3. Nakhman A. Еxponentially methods of summation of Fourier series. International Journal Of Applied And Fundamental Research. – 2013. – № 2 –URL: www.science-d.com/455-24312 (18.11.2013).
Nakhman A. D. EXPONENTIAL MEANS OF POWER SERIES OF FUNCTIONS OF CLASSES H(p/v)
. International Journal Of Applied And Fundamental Research. – 2014. – № 2 –
URL: www.science-sd.com/457-24561 (09.01.2025).