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If $f:[a,b]\to[a,c]$ is a strictly increasing piecewise linear map with $c<b$, then does it necessarily follow that $f^n(b)=f(f(f(...(b)...)))\to a$?

Brian Rushton
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1 Answers1

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No. Consider $f$ on $[-1, 1]$ defined by $f(x) = \begin{cases} x, & \text{if $-1 \le x\le 0$ } \\ x/2, & \text{if $0 \lt x \le 1$} \\ \end{cases}$

Then $f^n(b)=f^n(1) \rightarrow 0 $

John Douma
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