
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
A person has 10 friends and over the course of several days, invites some of them over in such a way that the group of friends in each instance is never repeated (some days he may invite no one). For how many days can he do this?

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