My question is primarily about this piano performance:
The number Pi is played with the right hand by mapping each digit to a note in the A minor scale:
0 1 2 3 4 5 6 7 8 9 G# A B C D E F G# A B
In the mean time the left hand arpeggiates certain chords. One chord generally lasts for two notes of the Pi melody. Here are the first few notes and the accompanying chords:
Digits: 3 1 4 1 5 9 2 6 5 3 5 8 9 7 9 3 2 3 8 4 6 2 6 4 3 3 8 3 2 7 9 5 0 2 8 8 4 1 9 7 1 ... Melody: C A D A E B B F E C E A B G#B C B C A D F B F D C C A C B G#B E G#B A A D A B G#A ... Chords: Am Dm C G7 C C E E Am Am Dm Dm C Am E E Am Am Dm E ...
I have not transcribed the whole song (over 100 digits) but so far I could not spot a repeating chord progression. I could neither find any pattern by which the chords could be deduced from the melody.
It may well be possible that the author used the chords that sounded good to him in the context of the song.
I was wondering however, if one could algorithmically determine the chords to go with the melody seeing that this song is potentially infinite.
Any help on this would be great! And if anyone can spot a pattern in the way chords are used that would be awesome.
This is mostly an experiment but I would also like to use it as an example in my upcoming talk on computer music.