Description:How many different musical chords, or scales, or rhythms, are there, and why are some more popular than others? Questions such as these can be answered using the tools of mathematical combinatorics, as explained in this fascinating book accessible to the high-school or undergraduate student of mathematics, or the musician with some math background. Mathematical concepts which appear include binomial coefficients, necklace counting, Pascal's triangle, the Fibonacci sequence, and Polya counting theory.