User:CompactStar/Super-pitch

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(Would have created in mainspace, but this is WIP and the explanation is currently somewhat vague)

Super-pitch is a quantity that is equal to the super-logarithm of frequency, just as pitch is the logarithm of frequency. Super-logarithms are an inverse function of tetration (iterated exponentiation), defined recursively as:

slogb(1) = 0

slogb(bx) = slogb(x) + 1

For example, slogb(b) = 1, slogb(bb) = 2 and slogb(bbb) = 3. Super-logarithms are only defined for inputs that are a power tower of the base (1, b, bb, bbb, etc.). However, there are various generalizations of the super-logarithm to other inputs, the most common of which is the linear approximation, defined as:

slogb(x) = x - 1 if 0 ≤ x ≤ l

slogb(bx) = slogb(x) + 1