On James and Jordan-von Neumann type constants and normal structure in Banach spaces

Abstract

The weakly convergent sequence coefficient ${\rm WCS}(X)$ is estimated by the James type constant $J_{X,t}(\tau)$, Jordan-von Neumann type constant $C_{t}(X)$ and the Domínguez Benavides coefficient $R(1,X)$, which enable us to obtain some sufficient conditions for normal structure. The results obtained in this paper are more general than other previously known sufficient conditions for normal structure.