Affiliation:
1. Department of Mathematics , I. Javakhishvili Tbilisi State University , 1 Chavchavadze ave. , Tbilisi 0128 , Georgia
Abstract
Abstract
Some statements connected with the
(
C
,
-
1
<
α
<
0
,
-
1
<
β
<
0
)
{(C,-1<\alpha<0,-1<\beta<0)}
summability
almost everywhere of double series with respect to block-orthonormal systems are
given. In particular, using the obtained results, we can determine Weyl multipliers for
establishing negative order summability of double series with respect to
Δ
p
,
q
{\Delta_{p,q}}
-ONS.
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(
C
,
-
1
<
α
<
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,
-
1
<
β
<
0
)
{(C,-1<\alpha<0,-1<\beta<0)}
-summability of single and double orthogonal series,
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On the
(
C
,
α
≥
0
,
β
≥
0
)
{(C,\alpha\geq 0,\;\beta\geq 0)}
-summability of double orthogonal series,
Studia Math. 81 (1985), no. 1, 79–94.