Delta-rational chord: Difference between revisions

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In practice these terms can loosely refer to approximations of mathematically exact PDR and FDR chords, for example in [[edo]] tunings.
In practice these terms can loosely refer to approximations of mathematically exact PDR and FDR chords, for example in [[edo]] tunings.
=== Facts ===
=== Facts ===
Let ''a'', ''b'' be positive integers and suppose gcd(''a'', ''b'') = 1. Let ''p'' > 1. Consider a MOS ''a'''''L'''''b'''''s'''{{angbr|p}} with generator range <math>I \subseteq (1, \sqrt{p})</math>, and consider a triple ('''0''', '''u''', '''v''') (representing a triad in the MOS), '''0''' < '''u''' < '''v'''. Let '''p''', '''g''' be a basis formally representing the MOS scale's period and the generator. Write  
Let ''a'', ''b'' be positive integers and suppose gcd(''a'', ''b'') = 1. Let ''p'' > 1. Consider a MOS ''a'''''L'''''b'''''s'''{{angbr|p}} with generator range <math>I \subseteq (1, \sqrt{p})</math>, and consider a triple ('''0''', '''u''', '''v''') (representing a triad in the MOS), '''0''' < '''u''' < '''v'''. Let '''p''', '''g''' be a basis formally representing the MOS scale's period and generator. Write  


<math>\begin{align}
<math>\begin{align}