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The term ''flought'' was coined by Inthar by evolving the Old English past participle ''(ġe)flohten'' of the verb ''fleohtan'' 'to weave; to plait' into a hypothetical Modern English word. It is cognate to the Modern English words ''plait'' and ''plexus''. | The term ''flought'' was coined by Inthar by evolving the Old English past participle ''(ġe)flohten'' of the verb ''fleohtan'' 'to weave; to plait' into a hypothetical Modern English word. It is cognate to the Modern English words ''plait'' and ''plexus''. | ||
== Properties == | == Properties == | ||
# The following is a necessary and sufficient condition for floughtenability. Let ''s'' be a scale with equave ''P'', <math>\mathcal{D}_k(s)</math> be the set of all ''k''-step intervals of ''s'', and Δ be a chord such that every interval of Δ falls within (0, ''P''). Then the polyoffset chord Δ floughtens ''s'' if and only if no nonunison (positive) interval in Δ falls within <math> | # The following is a necessary and sufficient condition for floughtenability. Let ''s'' be a scale with equave ''P'', <math>\mathcal{D}_k(s)</math> be the set of all ''k''-step intervals of ''s'', and Δ be a chord such that every interval of Δ falls within (0, ''P''). Then the polyoffset chord Δ floughtens ''s'' if and only if no nonunison (positive) interval in Δ falls within <math> [\min \mathcal{D}_k(s), \max \mathcal{D}_k(s)].</math> for any ''k'' = 0, ... len(''s'') - 1. | ||
# For any periodic scale s with equave E, if Δ is a polyoffset and Fl(s; Δ) exists, then Fl(s; Δ) = Fl(s; E - Δ) where E - Δ = {E - δ : δ ∈ Δ}. Nor does shifting any individual note in Δ by equaves change the associated flought scale. | # For any periodic scale s with equave E, if Δ is a polyoffset and Fl(s; Δ) exists, then Fl(s; Δ) = Fl(s; E - Δ) where E - Δ = {E - δ : δ ∈ Δ}. Nor does shifting any individual note in Δ by equaves change the associated flought scale. | ||
# Given an E-equivalent scale s, offsets δ within (0, min({step sizes in s})) are called ''small'' in the context of floughtening s. Small offsets are significant because the resulting flought scale mimics the underlying scale structure: if s is a circular word w(a1, a2, ..., an) then Fl(s; δ) uses the same circular word but with δ followed by the difference between δ and every step size in w, namely w(δ b1, δ b2, ..., δ bn) where bi = ai - δ. | # Given an E-equivalent scale s, offsets δ within (0, min({step sizes in s})) are called ''small'' in the context of floughtening s. Small offsets are significant because the resulting flought scale mimics the underlying scale structure: if s is a circular word w(a1, a2, ..., an) then Fl(s; δ) uses the same circular word but with δ followed by the difference between δ and every step size in w, namely w(δ b1, δ b2, ..., δ bn) where bi = ai - δ. | ||