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Difference between revisions of "1993 IMO Problems/Problem 5"

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Find as ≈ Ftheftics
 
Find as ≈ Ftheftics
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==Video solution==
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https://youtu.be/IfCBp0608p8

Revision as of 02:36, 11 July 2020

Problem

Let $\mathbb{N} = \{1,2,3, \ldots\}$. Determine if there exists a strictly increasing function $f: \mathbb{N} \mapsto \mathbb{N}$ with the following properties:

(i) $f(1) = 2$;

(ii) $f(f(n)) = f(n) + n, (n \in \mathbb{N})$.

Solution

Here is my Solution https://artofproblemsolving.com/community/q2h62193p16226748

Find as ≈ Ftheftics

Video solution

https://youtu.be/IfCBp0608p8

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