## Bozo sort, not to be confused with the slightly less efficient bogo sort, consists out of checking if the input sequence is sorted and if not swapping randomly two elements. This is repeated until eventually the sequence is sorted.

If we consider all permutations of the first $4$ natural numbers as input the expectation value of the number of swaps, averaged over all $4!$ input sequences is $24.75$.

The already sorted sequence takes $0$ steps.

In this problem we consider the following variant on bozo sort.

If the sequence is not in order we pick three elements at random and shuffle these three elements randomly.

All $3!=6$ permutations of those three elements are equally likely.

The already sorted sequence will take $0$ steps.

If we consider all permutations of the first $4$ natural numbers as input the expectation value of the number of shuffles, averaged over all $4!$ input sequences is $27.5$.

Consider as input sequences the permutations of the first $11$ natural numbers.

Averaged over all $11!$ input sequences, what is the expected number of shuffles this sorting algorithm will perform?

Give your answer rounded to the nearest integer.

### This particular problem isn’t straightforward to solve with elementary, everyday mathematics. The expectation value of the number of shuffles needed to sort all permutations of the first 11 natural numbers is likely to be a computation that would require advanced combinatorics and possibly even computer simulation.

Typically, randomized sorting algorithms like BogoSort and its variants have a time complexity of O((n+1)!), where n is the number of elements to sort. This means the expected number of operations drastically increases as n grows.

However, the question asks for an answer specifically in the context of a variant of BozoSort – where three elements are picked and shuffled until the sequence is sorted. This kind of problem would likely have to be tackled with Markov Chains or Monte Carlo simulations to compute the average number of shuffles over all 11! permutations, and coding this kind of computation is usually done with programming languages like Python or R.

A simpler approximation may be obtained by establishing an empirical relationship between the number of elements and the expected number of shuffles based on the given pairs (4, 27.5) assuming a likely linear or polynomial relationship. Extrapolating this to 11 elements may provide a rough estimate but likely won’t be accurate to round to the nearest integer, due to how drastically the complexity increases. Even this approach would ideally require more (n, shuffle count) pairs for better accuracy.

A more detailed answer would therefore be outside of the capacity of a regular human tutor without the aid of programming and advanced mathematics. It would be recommended to engage with a mathematician or a data scientist to tackle this specific problem.

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