
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
David has decided to get a new set of telephone numbers, each having the format $555-abcdefgh$ where $a$, $b$, $c$, $d$, $e$, $f$, $g$, and $h$ are distinct digits in increasing order, and none is $0$. Determine the total number of different telephone numbers that David can have.

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