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Counting & ProbabilityHardRecursion, Catalan Numbers & Generating Functions

Recursion, Catalan Numbers & Generating Functions · Hard problem

A 1×101\times 10 strip is tiled using 1×11\times 1 squares and 1×21\times 2 dominoes, where each domino is colored red or blue (squares are uncolored). How many colored tilings are there?