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Difficulty: 3 of 5 Latest: Alternating Differences
Let X1, X2, X3, ..., Xn be a permutation of the integers 1,2,3,...,n.

Consider the sum:
abs(X1-X3) + abs(X2-X4) + abs(X3-X5) + ... + abs(Xn-2-Xn).

What is the mean value of this sum taken over all possible permutations?

(No Solution Yet, 1 Comments) Submitted on 2023-12-07 by K Sengupta   
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