The enigmatic Canon 1 à 2 from J. S. Bachs Musical Offering (1747), The manuscript depicts a single musical sequence that is to be played front to back and back to front.
I have no doubt that Johann Sebastian would have made an excellent software developer! The programming mindset required for this highly technical composition reflects as much. To reiterate – the single line of music plays with itself! The first voice plays front to back and the second voice plays back to front – or vice versa.
mathemusic 