Ordinarily, Mancala is a two-player game where each has a store. For this puzzle, there is no opponent so the seeds cannot go past the store. As a consequence, pit A can never have more than 1 seed, pit B can never have more than 2 seeds, etc.
The question is for a given number of pits, n, what's the maximum number of seeds, S(n) that a player can start and with optimum play drop the last seed in the store with each move?
For example S(2)=3. In the diagram, B and A are the pits, and X is the store:
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Derive a formula for S(n).
If a reasonable formula is not possible, try to give an approximation for large n.