
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 A be a non-empty subset of the set of integers {1, 2, 3, 4, 5} and k ∈ A. If k - 1 ∉ A and k + 1 ∉ A, then k is called an "isolated element" of A. Determine the number of subsets of A that have exactly one isolated element.

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