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  • 已知数列\(\{a_{n}\}\),\(\{b_{n}\}\)满足\(b_{n}=a_{n+1}-a_{n}(n=1,2,3,…)\).
    \((1)\)若\(b_{n}=10-n\),求\(a_{16}-a_{5}\)的值;
    \((2)\)若\(b_{n}=(-1)^{n}(2^{n}+2^{33-n})\)且\(a_{1}=1\),则数列\(\{a_{2n+1}\}\)中第几项最小?请说明理由;
    \((3)\)若\(c_{n}=a_{n}+2a_{n+1}(n=1,2,3,…)\),求证:“数列\(\{a_{n}\}\)为等差数列”的充分必要条件是“数列\(\{c_{n}\}\)为等差数列且\(b_{n}\leqslant b_{n+1}(n=1,2,3,…)\)”.
    【考点】等差数列的通项公式,等差数列的判定与证明,等差数列的性质,等差数列的概念
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    【解答】请登陆后查看
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