Special issue: recent progress on iterative methods for large systems of equations

A Workshop on Numerical Algebra, Algorithms, and Analysis in honor of Professor Ken Hayami’s 60th birthday was held at the National Institute of Informatics, Tokyo, Japan, on January 11–12, 2016. Over 30 participants including 13 invited speakers from China, Germany, Japan, Spain, and USA presented talks, shared ideas, and had lively discussions on a wide variety of topics on iterative methods. http://www.cs. tsukuba.ac.jp/∼morikuni/WNA3KH/ This special issue consists of 9 papers submitted by some of the speakers and participants of the workshop. They have been refereed under the standard procedures for papers submitted to this journal. The papers are: