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$301. $ 已知\(\displaystyle a_n = \frac{3^n+1}{4}\)\(S_n = \sum \limits_{k=1}^n a_k\),证明:当\(n \ge 2\)时,\(\displaystyle \frac{8}{3}(n+1)S_n > (n+1)C_{n+1}^02^n + n C_{n+1}^1 2^{n-1} + \cdots + C_{n+1}^n 2^0\)

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