
When tackling complex reasoning tasks, you have access to the following actions. Use them as needed to progress through your thought process.

[ASSESS]

[ADVANCE]

[VERIFY]

[SIMPLIFY]

[SYNTHESIZE]

[PIVOT]

[OUTPUT]

You should strictly follow the format below:

[ACTION NAME]

# Your action step 1

# Your action step 2

# Your action step 3

...

Next action: [NEXT ACTION NAME]


system
Given a sequence $\{a_n\}$ satisfying $a_1=1$, $a_{n+1}= \frac {2a_n}{a_n+2}$, and let $C_n= \frac {2^n}{a_n}$, then the sum of the first $n$ terms of the sequence $\{C_n\}$, $C_1+C_2+\ldots+C_n=$ __________.

Present the answer in LaTex format: \boxed{Your answer}
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