
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 postal worker is responsible for delivering mail to the twenty houses on the west side of Maple Street. It's observed that no two adjacent houses receive mail on the same day and no more than two consecutive houses go without receiving mail. Furthermore, the sequence of mail delivery always starts with a house receiving mail. How many different patterns of mail delivery are possible?

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