# cryptarithm

A cryptarithm is a number puzzle in which a group of arithmetical operations has some or
all of its digits replaced by letters or symbols, and where the original
digits must be found. In such a puzzle, each letter or symbol represents
a unique digit. The first example appeared in *American Agriculturist* in 1864. Specific types of cryptarithm include the alphametic,
the digimetic, and the skeletal
division. A **digimetic** is
a cryptarithm in which digits are used to represent other digits.