
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
If a function $f(x)$ has the property: $f\left( \frac {1}{x}\right)=-f(x)$, then $f(x)$ is said to satisfy the "inverse negative" transformation. Among the following four functions:  
1. $f(x)=\log_{a}x$ ($a > 0$ and $a\neq 1$);  
2. $f(x)=a^{x}$ ($a > 0$ and $a\neq 1$);  
3. $y=x- \frac {1}{x}$;  
4. $f(x)= \begin{cases} x, & (0 < x < 1) \\ 0, & (x=1) \\ - \frac {1}{x}, & (x > 1) \end{cases}$.  

The serial numbers of all functions that satisfy the "inverse negative" transformation are ______.

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