I am neither a mathematician nor a music pro. But it's obvious that (any) music consists of a great variety of parallel ('chords') and serial ('melody') patterns. Math and music are closer to each other than we might believe.
Almost all of these parameters (tune, rhythm, note length, attack etc. etc.) can be modified, either by the human player (lips, finger) or a machine (Flute, Synthesizer or whatever).
Fractals or other iterative process open a wide range of mathematically defined methods of alterating patterns. And these evolving patterns can be used to create or to change a melody, a rhythmic pattern, the colour of a sound and so on.
Of course, an "uncontrolled" machine produces a lot of crap. But the more "switches" for the iterative process you can control (by software e.g.) the better results you might get: somekind of flowing music slowly (or drastically) changing or even 'morphing'.
@ Fjord: (the one and only) Johann Sebastian Bach experimented with music-mathematical techniques, Terry Riley, Steve Reich or Phil Glass used iterative techniques in their 20-century-music; a lot of indigene African music can be described by iterative process. And Techno has elements in it.
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