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            • 1.

              在数列\(\left\{ {{a}_{n}} \right\}\)中,\({{a}_{{1}}}{+2}{{a}_{2}}+{{2}^{2}}{{a}_{3}}+\cdots +{{2}^{n-1}}{{a}_{n}}=(n\cdot {{2}^{n}}-{{2}^{n}}+1)\ t\)对任意\(n\in {{N}^{*}}\)成立,其中常数\(t > 0.\)若关于\(n\)的不等式\(\dfrac{1}{{{a}_{2}}}+\dfrac{1}{{{a}_{4}}}+\dfrac{1}{{{a}_{8}}}+\cdots +\dfrac{1}{{{a}_{{{2}^{n}}}}} > \dfrac{m}{{{a}_{1}}}\)的解集为\(\{n|n\geqslant 4,n\in {{N}^{*}}\}\),则实数\(m\)的取值范围是                   

            • 2.

              已知数列\(\{a_{n}\}\)的首项\(a_{1}=1\),前\(n\)项的和为\(S_{n}\),且满足\(2a_{n+1}+S_{n}=2(n∈N^{*})\),则满足\(\dfrac{1\mathrm{\ }001}{1\mathrm{\ }000} < \dfrac{S_{2n}}{S_{n}} < \dfrac{11}{10}\)的\(n\)的最大值为              \(.\) 

            • 3.

              数列\(\{a_{n}\}\)满足\({{a}_{n+1}}=\dfrac{{{a}_{n}}}{2{{a}_{n}}+1}\),\({{a}_{3}}=\dfrac{1}{5}\)则\(a_{1}=\)________.

            • 4.

              数列\(\{a_{n}\}\)满足\(a_{1}=1\),\(a_{n+1}=(n^{2}+n-λ)a_{n}(n=1,2,…)\),\(λ\)是常数.

              \((1)\)当\(a_{2}=-1\)时,求\(λ\)及\(a_{3}\)的值;

              \((2)\)是否存在实数\(λ\)使数列\(\{a_{n}\}\)为等差数列?若存在,求出\(λ\)及数列\(\{a_{n}\}\)的通项公式;若不存在,请说明理由.

            • 5.

              已知数列\(\{a_{n}\}\)满足\(a_{n+2}=a_{n+1}-a_{n}\),且\(a_{1}=2\),\(a_{2}=3\),则\(a_{2018}\)的值为________.

            • 6. 已知数列\(\{ a_{n}\}\)的前\(n\)项和为\(S_{n}\),且\(S_{n}{=}a_{n}{+}n^{2}{-}1(n{∈}N^{{*}})\).
              \((1)\)求数列\(\{ a_{n}\}\)的通项公式;
              \((2)\)定义\(x{=[}x{]+ < }x{ > }\),其中\({[}x{]}\)为实数\(x\)的整数部分,\({ < }x{ > }\)为\(x\)的小数部分,且\(0{\leqslant < }x{ > < }1\),记\(c_{n}{= < }\dfrac{a_{n}a_{n{+}1}}{S_{n}}{ > }\),求数列\(\{ c_{n}\}\)的前\(n\)项和\(T_{n}\).
            • 7. 已知数列\(\{a_{n}\}\)的前\(n\)项和为\(S_{n}\),且满足\(S_{n}=2a_{n}-2\).
              \((\)Ⅰ\()\)求数列\(\{a_{n}\}\)的通项公式;
              \((\)Ⅱ\()\)设函数\(f(x)=( \dfrac {1}{2})^{x}\),数列\(\{b_{n}\}\)满足条件\(b_{1}=2\),\(f(b_{n+1})= \dfrac {1}{f(-3-b_{n})}\),\((n∈N^{*})\),若\(c_{n}= \dfrac {b_{n}}{a_{n}}\),求数列\(\{c_{n}\}\)的前\(n\)项和\(T_{n}\).
            • 8.
              已知数列\(\{a_{n}\}\)中,\(a_{1}=1\),\( \dfrac {a_{n+1}}{a_{n}}= \dfrac {n+1}{2n}\),则数列\(\{a_{n}\}\)的通项公式为 ______ .
            • 9.
              已知数列\(\{a_{n}\}\)的前\(n\)项和\(S_{n}=1-5+9-13+17-21+…+(-1)^{n-1}(4n-3)\),则\(S_{11}=(\)  \()\)
              A.\(-21\)
              B.\(-19\)
              C.\(19\)
              D.\(21\)
            • 10.

              在数列\(\{{{a}_{n}}\}\)中,\({{a}_{1}}=4,{{a}_{n+1}}-1=3({{a}_{n}}-1)\) ,则数列\(\left\{ {{a}_{n}} \right\}\)的通项公式\({{a}_{n}}=\) ______.

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