We are now in a position to understand certain musical terms from a physics perspective. The standing wave frequencies for this string are f1=320Hz, f2=2f1=640Hz, f3=3f1=960Hz, etc. This set of frequencies is called a harmonic series and it contains common musical intervals such as the octave (in which the ratio of frequencies of the two notes is 2:1) and the perfect fifth (in which the ratio of frequencies of the two notes is 3:2). Here f2 is one octave above f1, f3 is a perfect fifth above f2, and so on. Standing wave patterns with frequencies higher than the fundamental frequency are called overtones. The n=2 pattern is called the first overtone, the n=3 pattern is called the second overtone, and so on.

How does the overtone number relate to the standing wave pattern number, previously denoted with the variable n?