zbMATH — the first resource for mathematics

Examples
Geometry Search for the term Geometry in any field. Queries are case-independent.
Funct* Wildcard queries are specified by * (e.g. functions, functorial, etc.). Otherwise the search is exact.
"Topological group" Phrases (multi-words) should be set in "straight quotation marks".
au: Bourbaki & ti: Algebra Search for author and title. The and-operator & is default and can be omitted.
Chebyshev | Tschebyscheff The or-operator | allows to search for Chebyshev or Tschebyscheff.
"Quasi* map*" py: 1989 The resulting documents have publication year 1989.
so: Eur* J* Mat* Soc* cc: 14 Search for publications in a particular source with a Mathematics Subject Classification code (cc) in 14.
"Partial diff* eq*" ! elliptic The not-operator ! eliminates all results containing the word elliptic.
dt: b & au: Hilbert The document type is set to books; alternatively: j for journal articles, a for book articles.
py: 2000-2015 cc: (94A | 11T) Number ranges are accepted. Terms can be grouped within (parentheses).
la: chinese Find documents in a given language. ISO 639-1 language codes can also be used.

Operators
a & b logic and
a | b logic or
!ab logic not
abc* right wildcard
"ab c" phrase
(ab c) parentheses
Fields
any anywhere an internal document identifier
au author, editor ai internal author identifier
ti title la language
so source ab review, abstract
py publication year rv reviewer
cc MSC code ut uncontrolled term
dt document type (j: journal article; b: book; a: book article)
Almost-coercive matrix transformations. (English) Zbl 0732.40002
Following C. Eizen and G. Laush [Math. Jap. 14, 137-143 (1969; Zbl 0195.067)], a sequence-to-sequence matrix transformation A is said to be almost-coercive if the A transform of every bounded sequence is almost-convergent in the sense of G. G. Lorentz. By reference to the characterization that was given by J. P. Duran [Math. Z. 128, 75-83 (1972; Zbl 0235.40004)] for this type of matrices, the authors formalize corresponding conditions on series-to-sequence and series-to-series transformation matrices. (Yet, when detailing the result of Eizen and Laush, some condition - being claimed by Duran to be inadequate and thus rendering their theorem false - presumably is taken for an equivalent to Duran’s stronger one.) Theorem 2.4, while worked in the very terms of the Corollary to Theorem 1 (not given reference to, though), in Duran’s paper, is in fact its series-to-sequence version.
MSC:
40C05Matrix methods in summability