Triads
2:3:4 power chord / fifth chord
3:5:7 "major triad of the Bohlen–Pierce scale"
4:5:6 major chord
5:6:7 perfect diminished chord
6:7:9 "The lowest numbers producing a minor triad in the harmonic series (McIntyre 2002)"
6:8:9 suspended fourth chord
8:9:12 suspended second chord
10:12:15 minor chord "the first occurrence of a minor triad in the harmonic series"
16:19:24 false minor triad?
16:20:25 augmented triad
27:32:40 supertonic triad?
45:54:64 diminished triad
54:64:243 Pythagorean minor triad
64:81:96 Pythagorean minor triad
Tetrads
3:5:7:9 "the primary tetrad in the Bohlen-Pierce tuning system"
3:5:9:15 "anomalous saturated suspension" http://x31eq.com/ass.htm
3:7:9:21 "anomalous saturated suspension"
4:5:6:7 harmonic seventh chord
4:5:6:18 major seventh chord
5:6:7:9 half-diminished seventh
8:9:10:12 mu major chord
8:10:12:15 major/major seventh chord
10:12:15:18 minor seventh
12:16:17:18 dream chord
20:25:30:36 dominant seventh chord
25:30:36:45 half-diminished seventh
40:48:60:75 minor/major seventh chord
80:100:125:144 augmented seventh chord
Pentads
4:5:6:7:9 Dominant ninth chord
8:10:12:14:17 Dominant minor ninth chord
20:25:30:36:48 Dominant seventh sharp ninth chord
Hexads