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## 'Nonagon Tiling' printed from http://nrich.maths.org/

Several stimulating tilings
of the plane can be obtained by considering extensions and
modifications to the following procedure:

TO TILE :N
FD :N
REPEAT 3 [RT 15 FD :N]
LT 120 FD :N LT 75 FD :N
REPEAT 3 [LT 15 FD :N]
LT 165
END
Try TILE 40 (say)

This generates an
extraordinary equilateral nine sided tile which can be used to
create spiral tilings with one or more arms.

The diagram above shows the
start of one such spiral tiling.

Explore the possibilities
of this tile and formulate elegant programs to replicate the
tilings that you discover.

[Older readers are reminded
of the earlier poster designed by Leapfrog's Ltd in the 1980's]