
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
There are 21 different applications installed on a phone. In how many ways can six applications be selected for deletion so that among them there are three applications from the following six: \( T, V, F, T', V', F' \), but none of the pairs \( T, T' \), \( V, V' \), \( F, F' \) are included?

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