Let $a_n = 4n^3 + 6n^2 + 4n + 1.$  Find
\[a_8 + a_9 + a_{10} + \dots + a_{23}.\]
Question:
Let $a_n = 4n^3 + 6n^2 + 4n + 1.$  Find
\[a_8 + a_9 + a_{10} + \dots + a_{23}.\]
Answer:
Let's think step by step.

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Let $a_n = 4n^3 + 6n^2 + 4n + 1.$  Find
\[a_8 + a_9 + a_{10} + \dots + a_{23}.\]
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