convolution rule

convolution rule

[‚kän·və‚lü·shən ‚rül]
(mathematics)
The statement that C (p + q, r) is the sum over the index j from j = 0 to j = r of the quantity C (p, j) C (q, r-j), where, in general, C (n, r) is the number of distinct subsets of r elements in a set of n elements (the binomial coefficient). Also known as Vandermonde's identity.