e is a mathematical constant associated with the natural logarithm. Because pitch is logarithmic with respect to frequency, it might be of interest in xenharmony as well, where the name natave (a portmanteau of "natural" and "octave") is suggested. It is close to the JI intervals 8/3, 43/16, and 11/4, making it a rather sharp eleventh. Due to the limit definition of e, it also occurs as the limit of the following sequence: 2/1, two 3/2, three 4/3, four 5/4, five 6/5, etc.
- EDN, equal divisions of this interval