a. Find an equation for the number of terms of the longest such sequence for any positive integer n.
b. Find equations for the bounds (the first and last terms) of the longest such sequence for any positive integer n.
Hint: Once you have an equation for the number of terms, and for the first term of the sequence, the last term is simply one less than their sum.
Hint 2: Ducks have absolutely nothing to do with the problem.