  Periodic functions are of special importance in quantum computing,
particularly in applications of Shor's algorithm. We explore methods of
creating circuits for periodic functions to better understand their properties.
We introduce a method for constructing the circuit for a simple monoperiodic
function, that is one-to-one within a single period, of a given period p. We
conjecture that to create a simples periodic function of period p, where p is
an n-bit number, one needs at most n Toffoli gates.
