Forward difference - Rosetta Code
https://rosettacode.org/wiki/Forward_differenceTask. Provide code that produces a list of numbers which is the n th order forward difference, given a non-negative integer (specifying the order) and a list of numbers. The first-order forward difference of a list of numbers A is a new list B, where B n = A n+1 - A n. List B should have one fewer element as a result. The second-order forward difference of A will be: