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#86b6bbc3-ecc3-4d9e-ae05-be5f97103c56基础解答题数列求和方法数列

25.(2023•铜陵三模)已知数列{an}\{a_{n}\}的前nn项和SnS_{n}满足(n+3)Sn=nSn+1(nN+)(n+3)S_{n}=nS_{n+1}(n\in N_{+}),且a1=2a_{1}=2
(1)求数列{an}\{a_{n}\}的通项公式;
(2)求证:1a14+1a24+1a34++1an4>2n+12\frac{1}{\sqrt[4]{{a}_{1}}}+\frac{1}{\sqrt[4]{{a}_{2}}}+\frac{1}{\sqrt[4]{{a}_{3}}}+\cdot \cdot \cdot +\frac{1}{\sqrt[4]{{a}_{n}}}>2\sqrt{n+1}-2