This indicator has been described in Stocks&Commodities, January 2000.
Formula:
MMM = MA+6*Slope/K, where
MA - MVA(Price) with [Length] number of periods,
Slope(i) = Sum(Price[i-j+1]*(Length-Factor)/2), Factor = 1+2*(j-1) for j=1..Length,
K = Length*(Length+1).
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