What is the recursive relation showing the possible ways of putting n = $2^k -1$ elements in a stack where always the ith element is in ith place(the element number one is always in first place in the stack). we define the amount of element i, $X(i)$. Always $X(2i)$ or $X(2i+1)$ should not be less than $X(i)$.($X(2i) orX(2i + 1) >= X(i)$) and the minimum amount is 1 unit and maximum amount is n = $2^k -1$ unit.
*In the original problem, the question asked of possible ways to make a syrup with fixed order of elements.