deletions | additions       diff --git a/section_Challenegs_in_Bushy_Trees__.tex b/section_Challenegs_in_Bushy_Trees__.tex  index 0129e3b..3809305 100644  --- a/section_Challenegs_in_Bushy_Trees__.tex  +++ b/section_Challenegs_in_Bushy_Trees__.tex 
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$$S(N) = \begin{cases}   1 & \text{if $N = 1$}; \\  \sum_{i=1}^{N}$ \sum_{i=1}^{N}  & \text{if $ N \ne 0$}; \\ $$ Therefore the number of possible permutations are $S(N)*N!$ . Unlike left-deep tree case, estimating the cost for all the possible bushy trees is computationally infeasible for moderately large N. Therefore it is required to come with a heuristic to select set of permutations for cost computations.Some heuristics considered are