limma of 256/243. The difference between the tone and the limma is the major semitone or apotome ("part cut off") of 2187/2048. Although the limma and the apotome are both represented by one step of 12-pitch equal temperament, they are not equal in Pythagorean tuning, and their difference, 531441/524288, is known as the Pythagorean comma. Contrast with modern nomenclature There is a one-to-one correspondence between interval names (number of scale steps + quality) and frequency ratios. This contrasts with equal temperament, in which intervals with the same frequency ratio can have different names (e.g., the diminished fifth and the augmented fourth); and with other forms of just intonation, in which intervals with the same name can have different frequency ratios (e.g., 9/8 for the major second from C to D, but 10/9 for the major second from D to E). See also Generated collection Just intonation List of meantone intervals List of intervals in 5-limit just intonation Shí-èr-lǜ Whole-tone scale References External links Neo-Gothic usage by Margo Schulter 3-limit tuning and intervals cs:Ditón de:Ditonus es:Ditono eo:Ditono nl:Ditonus ru:Дитон