
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
From ten piano keys selected, choosing 3, 4, 5, ..., 10 keys to press at the same time can produce a chord. If there is one different key, a different chord is produced. The number of such different chords is (answer in digits).

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