Function in Python to approximate the Sierpinski Triangle
sqrt.ch

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def stcurve(n, step, sign, turtle):
    if n == 0:
        turtle.goForward(step)
        return
    stcurve(n - 1, step, -sign, turtle)
    turtle.turnAngle(sign * 60)
    stcurve(n - 1, step, sign, turtle)
    turtle.turnAngle(sign * 60)
    stcurve(n - 1, step, -sign, turtle)


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n: order or depth of the curve, for the graph shown, n = 10
step: length of the move, typically dependent on n; to obtain a graph with simple numbers, step = 1, is not the worst choice
sign: ensures to have the right orientation of the curve of order n-1
turtle: can be any (of your own pets) that can move forward (step) and turn (Angle)
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Normally, two functions are implemented to create this curve. This means for a «Lindenmayer System»:

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¦ Start with: F
¦ Rule: A-F-A, where A ist replaced by:
¦ Replacement-Rule: F+A+F
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Instructions:
F: Go Forward
A: Go Forward and call Replacement-Rule
-: Turn Left by 60°
+: Turn Left by -60°

https://www.sqrt.ch/mathematik.html#ls