Step 1:

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The series is $\"\"$ .

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If $\"\"$ convergence, then $\"\"$ .

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Find $\"\"$ .

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$\"\"$

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$\"\"$

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$\"\"$

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$\"\"$

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$\"\"$ .

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$\"\"$ .

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Therefore, the sequence is divergent.

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Solution:

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$\"\"$ is divergent.