# Solution: 2008-2 Strange representation

Byoung Chan Lee (이병찬)

Prove that if x is a real number such that $$0<x\le \frac12$$, then x can be represented as an infinite sum

$$\displaystyle x=\sum_{k=1}^\infty \frac{1}{n_k}$$,

where each $$n_k$$ is an integer such that $$\frac{n_{k+1}}{n_k}\in \{3,4,5,6,8,9\}$$.

The best solution was submitted by Byoung Chan Lee (이병찬), 수리과학과 2007학번. Congratulations!

Click here for his Solution of Problem 2008-2.

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