4 results for “Z. A. Hassanain”

Research ArticleOpen accessIn the author namesS-Numbers of Weighted Shift Operators on P-Summable Formal Entire Functions of M-VariablesNashat Faried, Z.A. Hassanain, H. Abd El Ghaffar, A. LokmanThe idea of multiplying a formal Taylor power series by z to make a right shift operator on the space of all square summable sequences of real numbers was due to A.L. Shield. In this work, we consider Taylor power series in m-variables and we give upper and lower estimations of s-numbers for multiplication of m- right weighted shift operators. … …Journal of Mathematics and Statistics, Vol. 15, Issue 1 · 3 May 2019 · 6,922 accessesView PDF Cite

Research ArticleOpen accessIn the author namesHypercyclic Functions for Backward and Bilateral Shift OperatorsN. Faried, Z. A. Hassanain, A. MorsyProblem statement: Giving conditions for bilateral forward and unilateral backward shift operators over the weighted space of p-summable formal series to be hypercyclic. This provides a generalization to the case of Hilbert space. Approach: We used hypercyclicity criterion and some preliminary concepts for formal Laurent series and formal power series. Moreover we got benefits of some duality properties of above … …Journal of Mathematics and Statistics, Vol. 5, Issue 3 · 30 Sep 2009 · 8,184 accessesView PDF Cite