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  • 题型:解答题 题类:模拟题 难易度:中档

    设\(\{a _{n} \}\)是等差数列,\(\{b _{n} \}\)是等比数列.已知\(a _{1} =1\),\(b _{1} =2\),\(b _{2} =2a _{2}\),\(b _{3} =2a _{3} +2\).
    \((1)\)求\(\{a _{n} \}\)和\(\{b _{n} \}\)的通项公式;
    \((2)\)数列\(\{c _{n} \}\)满足\(c _{n} = \begin{cases} {1,n=2^{k}} \\ {a_{n},n\neq 2^{k}}\end{cases} (k∈N)\),设数列\(\{c _{n} \}\)的前\(n\)项和为\(S _{n}\),求\(S _{2^{n}}\).
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