This book publishes original research chapters on the theory of approximation by positive linear operators as well as theory of sequence spaces and illustrates their applications. Chapters are original and contributed by active researchers in the field of approximation theory and sequence spaces. Each chapter describes the problem of current importance and summarizes ways of their solution and possible applications which improve the current understanding pertaining to sequence spaces and approximation theory. The presentation of the articles is clear and self-contained throughout the book.

Autorentext

S. A. Mohiuddine is a full professor of Mathematics at King Abdulaziz University, Jeddah, Saudi Arabia. An active researcher, he has co-authored four books: Convergence Methods for Double Sequences and Applications (Springer, 2014), Advances in Summability and Approximation Theory (Springer, 2018), Soft Computing Techniques in Engineering, Health, Mathematical and Social Sciences, Sequence Space Theory with Applications, and a number of chapters in several edited book and has contributed more than 150 research papers to various leading journals. He is the referee of many scienti c journals and member of the editorial board of various scienti c journals, international scienti c bodies and organizing committees. He has visited several international universities including Imperial College London, UK. He was a guest editor of a number of special issues for Abstract and Applied Analysis, Journal of Function Spaces and Scienti c World Journal. His research interests are in the elds of sequence spaces, statistical convergence, matrix transformation, measures of non-compactness and approximation theory. His name has been appeared in the list of World's Top 2% Scientists (for the three consecutive years 2020-2022) prepared by Stanford University, California, through Scopus data provided by Elsevier.

Bipan Hazarika is a Professor at Department of Mathematics, Gauhati University, Guwahati, Assam. Earlier, he worked at Rajiv Gandhi University, Arunachal Pradesh, India from 2005 to 2017. He was Professor at Rajiv Gandhi University up to 2017. He received an M.Sc. and Ph.D. from Gauhati University, Guwahati, India. His main research areas are sequences spaces, summability theory, applications of xed point theory, fuzzy analysis, and non-absolute integrable function spaces. He published more than 160 research articles in several renowned international journals. He is a regular reviewer of more than 50 different journals published by Springer, Elsevier, Taylorand Francis, Wiley, IOS Press, World Scienti c, American Mathematical Society, IEEE, De Gruyter, etc. He published books on Differential Equations, Differential Calculus and Integral Calculus. Recently he edited the following books: "Sequence Spaces Theory and Applications, Chapman and Hall/CRC" and "Fixed Point Theory and Fractional Calculus: Recent Advances and Applications, Springer". He is an editorial board member of more than 6 international journals and guest editor of a special issue named "Sequence spaces, Function spaces and Approximation Theory" of the Journal of Function Spaces.

Hemant Kumar Nashine is a professor at the VIT Bhopal University, Madhya Pradesh, India. As a Nehru-Fulbright fellow, he is a visiting professor at the University of Johannesburg, South Africa. He specializes in nonlinear functional analysis and its applications to differential and integral equations, and nonlinear matrix equations. He has more than 150 peer-reviewed publications to his credit, as well as the author of several chapters. He is an editor and a lead editor for a number of international publications, as well as a member of a number of mathematical societies.