A geometric sequence is a set of numbers with a pattern, basically. A very straightforward example of this is the octave (a common term in music), where each sequential octave is double the frequency of the previous octave. So how could we represent this using a sequence? It's simple. Sequential octaves are a Geometric Sequence of the form:
where a=440Hz, r=2, n=-4 and N=4. Plugged into the above sequence, these values will give you the frequencies of every octave in music based off 440Hz, A4(middle A). The sequence ranges from A0 at 27.5 Hz up to A9 at 14080Hz, which are the note A in each of the 10 octaves used in modern music.
