Tetratonic

The two Creek Indian "Duck Dance Songs" from the north- eastern United States illustrate the use of a tetratonic scale, A, C, D, E ( Example 5a ), and a pentatonic scale, A, C, D, E, G ( Example 5b ).

Pentatony can also come about through the simple complement and melodic development of the tetratonic melodic nucleus.

This four-note pattern is called a tetratonic, or also sometimes referred to as a melodic structures (by saxophonist Jerry Bergonzi, and others). […] This is powerful because applying this tetratonic formula R235 or R345, you have something that works(!) to play on every chord change and on every beat.

Of course such tetratonic music is capable of powerful expression in its own particular mood but there has apparently been no attempt to evolve form as such.

Beyond these areas Sasak music largely diverges from pélog and slendro tonality, and there are a number of tetratonic forms — in compositions for gamelan beleq and kamput, for example.

Tetratonic music was noted as common in Polynesia and Melanesia.

PHOSPORUS/ELECTRON-MOLECULE COLLISIONS: High temperature negative ions, Electron impact study of tetratonic phosphorus vapor

This tetratonic polymer proved to be more active than any of the tritonic polymers, showing the maximal inhibition recordable under standard test conditions.