Relaxed Halpern type iteration schemes for sequences of nonexpansive mappings in ${\rm CAT}(0)$ spaces

Abstract

Under weaker conditions on parameters, we prove strong convergence theorems of Halpern type iteration schemes for sequences of nonexpansive mappings in ${\rm CAT}(0)$ spaces. Since there is no assumption of the AKTT-condition imposed on the involved mappings, the results improve those of the authors with related researches.