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Alternating Differences (Posted on 2023-12-07)

Let X₁, X₂, X₃, ..., X_n be a permutation of the integers 1,2,3,...,n.

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

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

See The Solution Submitted by K Sengupta

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Comment 3 of 3 |

Posted by K Sengupta on 2023-12-16 08:12:32

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