Expected Runs in a Card Deck
A standard 52-card deck has 26 red cards and 26 black cards. You shuffle the deck thoroughly and lay the cards out in a row. A "run" is a maximal consecutive sequence of cards of the same color -- for example, if the first four cards are Red, Red, Red, Black, that is two runs (one of length 3 and one of length 1 so far).
What is the expected number of runs in the full 52-card sequence?
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