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Comments on the rate of convergence between Mann and Ishikawa iterations applied to Zamfirescu operators. (English) Zbl 1203.47076
Summary: In the work of G. V. R. Babu and K. N. V. V. Vara Prasad [Fixed Point Theory Appl. 2006, Article 49615 (2006); erratum ibid. 2007, Article ID 97986 (2007; Zbl 1106.47053)], the claim is made that Mann iteration converges faster than Ishikawa iteration when applied to Zamfirescu operators. We provide an example to demonstrate that this claim is false.
MSC:
47J25Iterative procedures (nonlinear operator equations)
47H10Fixed point theorems for nonlinear operators on topological linear spaces
References:
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