Demark Sequential - is an indicator that shows a structure of the trend, its start point and main turning points. And it check it's conditions on the beginning of the candle, so it will be never repainted.
This indicator hasn't any complex formulas, only some bars countdown, but it can be very helpful, especially with some levels indicator such as Fibo or Gann levels (like this).
Algorithm is so simple, but powerful:
Setup - starting when current bar closed higher (or lower for short) then cl