2 papers
math.FA2013
Some combinatorial principles for trees and applications to tree-families in Banach spaces
Costas Poulios, Athanasios Tsarpalias
Suppose that is a normalized family in a Banach space indexed by the dyadic tree . Using Stern's combinatorial theorem we extend important results from sequence…
math.FA1995
Convex unconditionality and summability of weakly null sequences
Spiros A. Argyros, S. Merkourakis, A. Tsarpalias
It is proved that every normalized weakly null \sq\ has a sub\sq\ which is convexly unconditional. Further, an Hierarchy of summability methods is introduced and with this we give…