Tuplets

Tuplets are grouped notes that have non standard durations.

duplets	2 notes instead of 3	2 * 3/8
triplets	3 notes instead of 2	3 * 1/6
quadruplet	4 notes instead of 3	4 * 3/16
quintuplets	5 notes instead of 2	4 * 1/10
quintuplets	5 notes instead of 3	4 * 3/20
quintuplets	5 notes instead of 4	5 * 1/5
sextuplets	6 notes instead of 2	6 * 1/12
sextuplets	6 notes instead of 4	6 * 1/6
septuplets	7 notes instead of 2	7 * 1/14
septuplets	7 notes instead of 3	7 * 3/28
septuplets	7 notes instead of 4	7 * 1/7

Duplets, quadruplets and octuplets might be notated as subsequent dotted notes.