pentatonic scale
a pentatonic scale is a musical scale that has five notes per octave it has a relation to the heptatonic scale which is a seven notes per octave, pentatonic scales are found all around the world, they are divided into those with semitones (hemitonic) and those without (anhemitonic)
pentatonix is a musical group, they use a cappella group that got there name from the pentatonic scale in result they have five members a bass, a beat boxer who is a tenor, mezzo-soprano, a baritone, and a counter tenor.