Schönhage–Strassen algorithm

The Schönhage–Strassen algorithm is a fast multiplication algorithm for large integers. It is named after its inventors, Christoph Schönhage and Volker Strassen, who introduced it in 1971. The algorithm is significant in computational number theory and computer algebra systems because it offers a way to multiply very large integers more efficiently than the conventional grade-school multiplication method, or even faster than the classical Karatsuba multiplication algorithm.