Same pitched notes are called "interval 1" and there goes thirds, fifths, sevenths... All off-by-one in my base-offset-addressing mind... And then major vs. minor which creates all kinds of "aliased addresses"...
I'd really love a BASE-12 floating number representation. Like 4.00 for the middle C; Chords can be then represented by a tuple of such numbers -- major = [+0.04, +0.07] (some sequencers already do something like that and I'm far better at reading that kind of sequencer data than a sheet)