MathCastle
Counting & ProbabilitySuperchallengeExpected Value, Linearity & Advanced Probability

Expected Value, Linearity & Advanced Probability · Superchallenge problem

A permutation of {1,…,8}\{1,\dots,8\} is chosen uniformly at random. Find the expected number of cycles in its cycle decomposition.

The answer is a fraction mn\tfrac{m}{n} in lowest terms; find m+nm + n.