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This problem follows on from Twisting and Turning and More Twisting and Turning in which twisting has the effect of adding 1 and turning transforms any number into the negative of its reciprocal.

We can start at 0 and end up at any fraction of the form $$\frac{n}{n+1}$$ by following the sequence: twist, twist, twist, ... , twist, twist, turn, twist

eg. to end up at $\frac{4}{5}$:

twist, twist, twist, twist, twist, turn, twist

to produce:

$0, 1, 2, 3, 4, 5, \frac{-1}{5}, \frac{4}{5}$

Check you can reach $\frac{9}{10}$

The sequence twist, twist, turn, twist, twist, turn, twist, twist, turn, ... , twist, twist, turn, twistwill lead us
from 0 to all the fractions of the form $$\frac{1}{n}$$ eg. to end
up at $\frac{1}{5}$ (and $\frac{1}{2}$, $\frac{1}{3}$ and
$\frac{1}{4}$ along the way):

twist, twist, turn, twist, twist, turn, twist, twist, turn, twist, twist, turn, twist

to produce: 0, 1, 2, $\frac{-1}{2}$, $\frac{1}{2}$, $\frac{3}{2}$, $\frac{-2}{3}$, $\frac{1}{3}$, $\frac{4}{3}$, $\frac{-3}{4}$, $\frac{1}{4}$, $\frac{5}{4}$, $\frac{-4}{5}$, $\frac{1}{5}$

Check you can reach $\frac{1}{10}$

Can you find other sequences
of twists and turns that lead to special fractions?

Is it possible to start at 0 and end up at any fraction?