Original LUA oscillator: http://fxcodebase.com/code/viewtopic.php?f=17&t=58535.
Formulas:
DMA[i] = E*Price[i]+(1-E)*DMA[i-1], where
E = D*D,
D = C*2/31+(1-C)*2/3,
C=A/B,
A = Price[i] - Price[i-Length+1],
B = Sum(Price[i]-Price[i-1]) from (i-Length+1) to (i).
Download: