Italian Folk Multiplication Algorithm Is Indeed Better: It Is More Parallelizable

Abstract

Traditionally, many ethnic groups had their own versions of arithmetic algorithms. Nowadays, most of these algorithms are studied mostly as pedagogical curiosities, as an interesting way to make arithmetic more exciting to the kids: by applying to their patriotic feelings—if they are studying the algorithms traditionally used by their ethnic group—or simply to their sense of curiosity. Somewhat surprisingly, we show that one of these algorithms—a traditional Italian multiplication algorithm—is actually in some reasonable sense better than the algorithm that we all normally use—namely, it is easier to parallelize.