Superparticular ratio: Difference between revisions
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'''Superparticular''' numbers are ratios of the form <math>\frac{n+1}{n}</math>, or <math>1+\frac{1}{n}</math>, where n is a whole number greater than 0. | '''Superparticular''' numbers are ratios of the form <math>\frac{n+1}{n}</math>, or <math>1+\frac{1}{n}</math>, where n is a whole number greater than 0. | ||
The word "superparticular" has Latin etymology and means "above by one part". The equivalent word of Greek origin is "epimoric" (from επιμοριοσ, epimorios). | |||
These ratios have some peculiar properties: | These ratios have some peculiar properties: | ||
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Curiously enough, the ancient Greeks did not consider 2/1 to be superparticular because it is a [[Harmonic|multiple of the fundamental]] (the same rule applies to all natural harmonics in the Greek system). | Curiously enough, the ancient Greeks did not consider 2/1 to be superparticular because it is a [[Harmonic|multiple of the fundamental]] (the same rule applies to all natural harmonics in the Greek system). | ||
According to some sources, such as Thomas Taylor's [https://books.google.com.au/books?id=VuY3AAAAMAAJ Theoretic Arithmetic, in Three Books], define superparticular ratios as those for which the denominator divides into the numerator once, leaving a remainder of one. This is another explanation for why 2/1 does not qualify as superparticular, because 1 divides into 2 twice, leaving a remainder of 0. Taylor's book further describes generalizations of the superparticulars: superbiparticulars are those where the denominator divides into the numerator once, but leaves a remainder of two (such as 5/3), and double superparticulars are those where the denominator divides into the numerator twice, leaving a remainder of one (such as 5/2). One can go on and on, with e.g. triple supertriparticulars where both the divisions and the remainder are 3 (such as 15/4). More details can be found on this forum thread here: [http://forum.sagittal.org/viewtopic.php?f=4&t=410 Generalisation of the terms "epimoric" and "superparticular" as applied to ratios] | |||
== See also == | == See also == |