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A Cauchy criterion for the summability of an infinite integral

Published online by Cambridge University Press:  20 January 2009

B. Thorpe
Affiliation:
Department of Pure MathematicsThe UniversityBirminghamB152TT
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If a ∈ L(1, T) for every finite T>1, then we say that the infinite integral a(u)du is convergent with sum s if a(u)du = s. It is well known that a necessary and sufficient condition for a(u)du to be convergent (with some finite sum s) is that Cauchy's criterion,

holds. The object of this note is to obtain a similar result for summability (C, α) of a(u) du which reduces to Cauchy's criterion in the case of convergence. The corresti ponding problem for summable series has been treated by A. F. Andersen in (1).

Type
Research Article
Copyright
Copyright © Edinburgh Mathematical Society 1980

References

REFERENCES

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