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The wise men want to survive

Source: 239 School Open MO, 2023, Senior league, Problem 1

April 1, 2023
combinatoricswinning strategy

Problem Statement

There are nn{} wise men in a hall and everyone sees each other. Each man will wear a black or white hat. The wise men should simultaneously write down on their piece of paper a guess about the color of their hat. If at least one does not guess, they will all be executed.
The wise men can discuss a strategy before the test and they know that the layout of the hats will be chosen randomly from the set of all 2n2^n layouts. They want to choose their strategy so that the number of layouts for which everyone guesses correctly is as high as possible. What is this number equal to?