William A Stein

William Arthur Stein (born February 21, 1974 in Santa Barbara, California) is a professor of mathematics at the University of Washington.

He is known as the lead developer of SageMath. Stein is currently doing computational and theoretical research into the problem of computing with modular forms and the Birch and Swinnerton-Dyer conjecture. He is considered "a leading expert in the field of computational arithmetic".