1. The problem statement, all variables and given/known data For formatting sake Ive copied a picture of the problem and attached it here: http://i.imgur.com/kOjTy.png Im not worried about the coding part right now I feel I can handle that, my main issue is trying to understand how the values in the summation are derived. It seems simple enough, but I cant seem to grasp how they got the 10 values in the example there. Once I understand the summation, the coding should be easy. I just need a bit of guidance in how it all's working. 2. Relevant equations Cn+1 = Ʃ Ck Cn-k from k = 0 to n 3. The attempt at a solution Obviously C0 = 1 Beyond that, here's what my understanding of it seems to be: For C1 k starts at 0 C1 = C0 * C1-0 + C1 * C1-1 but this is where I get confused.