The connections between mathematics and conceptual art are not obvious. Mathematics would seem the most precise of sciences, not governed by physical measurements and observations, but by calculation and proof. Conceptual art, on the other hand, is often ephemeral and ambiguous. Its very existence as art can be made open to question, a process that can be deliberately manifest in the work itself. In spite of these seeming differences, the similarities are numerous, natural and quite significant. This paper explores these connections and their importance to those with an interest in mathematics and art, including artists, educators and others involved in interdisciplinary practices. It briefly introduces the evolutionary history of conceptual art and the popular perception of what it is, defines the essence of conceptual art as a metaobject, and shows that mathematics is essentially conceptual, including the presence of a metaobject. In order for mathematical ideas to be accepted into artistic practice they must have an art theoretical position; that position is akin to the position that has been taken by conceptual art.