
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
Let's say that number A hides number B if we can remove several digits from A so that we get B (for example, number 123 hides numbers 1, 2, 3, 12, 13, and 23). Find the smallest natural number that hides all numbers from 2000 to 2021.

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