# Factorable function

### From Glossary

This has a recursive definition, relative to a
collection of *elementary operations* (e.g., sum, product) on
other factorable functions, starting with some set of *primitive
functions*. For example, starting with the power functions,
, for any and , and
allowing only the sum operation, we can
obtain all polynomials. The polynomial
*factors* into 3 parts.