
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 seven-digit phone number \(d_{1} d_{2} d_{3}-d_{4} d_{5} d_{6} d_{7}\) is called "memorable" if the initial three digits \(d_{1} d_{2} d_{3}\) match either the middle three digits \(d_{4} d_{5} d_{6}\) or the last three digits \(d_{5} d_{6} d_{7}\) (it is possible for all three groups to be the same). Each digit can be one of the digits \(0,1,2,3,\cdots,8,9\). How many different "memorable" phone numbers are there?

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