There's this really cool piece I found that uses the harmonic set. It's called Sonata no 17 in D minor by this guy Beethoven. The way he uses the set really fascinates me, you never hear it all at once but most of the harmony is based on 3 and 4 note subsets of 7-32, specifically 7-32A. He frequently shifts between different transpositions of 3-11 but cleverly restricts them so that each one is built upon the notes of 7-32. You also get a lot of 4-27 and 3-10 in the piece which he explores quite nicely. I noticed he often uses 4-27B right before 3-11B but transposed such that the bass notes are 7 semitones away from each other. Sometimes he will repeat 4-27B to 3-11B at these transpositions over and over again, he seems to really like that sound! I wonder if there is a name for this technique of composition?

what does 5 1 mean?