Let’s consider a Menger sponge of order n which side length is L.
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On the schema, we can see that this sponge contains 20 Menger sponges of order n− 1 and with a side length 
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The recursive structure of the sponge is well shown.
The program:
to cube :l
if :counter=10000 [view3d]
# faces colors
localmake "colors [yellow magenta cyan blue]
# lateral faces
repeat 4 [setpencolor run item repcount :colors square :l right 90 forward :l left 90 rightroll 90]
# bottom
setpencolor red downpitch 90 square :l uppitch 90
forward :l downpitch 90 setpencolor green square :l uppitch 90 back :l
end
to square :c
globalmake "counter :counter+1
polystart
repeat 4 [forward :c right 90]
polyend
end
# Menger’s sponge
# p: recursion order
# l: side length of the cube
to menger :l :p
if :p=0 [cube :l] [
localmake "p :p-1
localmake "l :l/3
#front face
repeat 3 [menger :l :p forward :l] back 3*:l
right 90 forward :l left 90
menger :l :p forward 2*:l menger :l :p back 2*:l
right 90 forward :l left 90
repeat 3 [menger :l :p forward :l] back 3*:l
#right face
downpitch 90 forward :l uppitch 90
menger :l :p forward 2*:l menger :l :p back 2*:l
downpitch 90 forward :l uppitch 90
repeat 3 [menger :l :p forward :l] back 3*:l
left 90 forward :l right 90
menger :l :p forward 2*:l menger :l :p back 2*:l
left 90 forward :l right 90
repeat 3 [menger :l :p forward :l] back 3*:l
downpitch 90 back :l uppitch 90
menger :l :p forward 2*:l menger :l :p back 2*:l
downpitch 90 back :l uppitch 90
]
end
to sponge :p
clearscreen hideturtle globalmake "counter 0 3d setscreencolor 0 menger 800 :p
write [nombre penpaint polygone: ] print :counter
view3d
end
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This program has four procedures: