A functional congruence is a congruence of the form
 |
where 
and 
are both integer polynomials. Functional congruences
are sometimes also called "identical congruences" (Nagell 1951, p. 74).
Functional Congruence
See also
CongruenceExplore with Wolfram|Alpha
References
Nagell, T. "Algebraic Congruences and Functional Congruences." §22 in Introduction to Number Theory. New York: Wiley, pp. 73-76, 1951.Referenced on Wolfram|Alpha
Functional CongruenceCite this as:
Weisstein, Eric W. "Functional Congruence." From MathWorld--A Wolfram Resource. https://mathworld.wolfram.com/FunctionalCongruence.html