More Properties of the \((M, \lambda _n)\) Method and Cauchy Multiplication of Certain Summable Series

  • P. N. NatarajanEmail author


In the present chapter, more properties of the \((M, \lambda _n)\) method are established. For instance, it is proved that the set \(\mathcal {M}\) of all \((M, \lambda _n)\) methods is an ordered abelian semigroup and there are infinite chains of \((M, \lambda _n)\) methods from \(\mathcal {M}\). A few results on the Cauchy multiplication of certain summable series are also proved.


Radius of convergence Symmetric product Ordered Abelian Semigroup Infinite chain Iteration product 


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© Springer Nature Singapore Pte Ltd. 2017

Authors and Affiliations

  1. 1.Formerly of the Department of MathematicsRamakrishna Mission Vivekananda CollegeChennaiIndia

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