representationcount
A representationcount, often referred to as a representation count, is a function that assigns to a target object, typically an integer, the number of representations of that object by a fixed mathematical structure under specified criteria. The idea is to count how many distinct ways the object can be expressed within the given framework.
Common contexts include quadratic forms, sums of powers, partitions, and, in a broader sense, representations of
Classic examples include the representations of integers as sums of two or four squares. For the sum
Generating functions play a key role: the sequence r_Q(n) often appears as coefficients in the theta series