User:Xenwolf/Interval quartet

An observation, that could have some potential:

Four intervals, connected to each other by octave and fifth complements, form an interval quartet.

Examples

• 5/3 ↔ 6/5 ↔ 5/4 ↔ 8/5

Generalization

As can be observed in FJS names and Interval regions, the 4-part interconnection doesn't stop after intervals.

• m6 ↔ M3 ↔ m3 ↔ M6
• d6 ↔ A3 ↔ d3 ↔ A6
• the four interseptimal regions are the union set of certain interval quartets.