
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 the sequence $\{a_n\}$ satisfies: $a_1=a_2=1$, $a_n=1- \dfrac {a_1+a_2+a_3+\ldots+a_{n-2}}{4}$ $(n\geqslant 3,n\in\mathbb{N}^*)$, then $a_6=$ ______.

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