prb:PolyDiv:{\cpl :eq:poly_convo} and Remark 4.1.24 (Multiplication of polynomials): (4.1.25)
In the solution of PolyDiv there is this sum which starts at max{..} and stops at min{...} whereas in the lecture code, (4.1.25), there is the full sum from 0 to j. It would ne nice if the lecture code would either explain that the coefficients which are out of bound are zero, or just have the same expression as in the solution of the problem.