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            • 1.
              已知等差数列\(\{a_{n}\}\) 的前\(n\)项和为\(S_{n}\),\(a_{1}=λ\) \((\) \(λ > 0\) \()\),\(a_{n+1}=2 \sqrt {S_{n}}+1\) \((n∈N*)\).
              \((I)\)求 \(λ\) 的值;
              \((II)\)求数列\(\{ \dfrac {1}{a_{n}a_{n+1}}\}\) 的前 \(n\)项和\(T_{n}\).
            • 2.

              已知在数列\(\{a_{n}\}\)中,\(a_{1}=1\),\(a_{n+1}=2a_{n}+n-1(n∈N*)\),则其前\(n\)项和\(S_{n}=\)________.

            • 3.

              已知数列\(\{ a_{n}\}\)满足:\(a_{1}{=}2{ , }a_{n{+}1}{=}1{-}\dfrac{1}{a_{n}}\),设数列\(\{ a_{n}\}\)的前\(n\)项和为\(S_{n}\),则\(S_{2017}{=}(\)  \()\)

              A.\(1007\)                         
              B.\(1008\)                         
              C.\(1009{.}5\)
              D.\(1010\)
            • 4. 设数列\(\left\{ {{a}_{n}} \right\}\)是等差数列,\({{a}_{3}}=5,{{a}_{5}}-2{{a}_{2}}=3\) ,数列\(\left\{ {{b}_{n}} \right\}\)为等比数列,满足\({b}_{1}=3,公比q=3 \)
              \((1)\)求数列\(\left\{ {{a}_{n}} \right\}\)和\(\left\{ {{b}_{n}} \right\}\)的通项公式;
              \((2)\)设\({{c}_{n}}={{a}_{n}}\cdot {{b}_{n}}\) ,设\({{T}_{n}}\)为\(\left\{ {{c}_{n}} \right\}\)的前\(n\)项和,求\({{T}_{n}}\) \(.\) 
            • 5.

              设数列\(\left\{ {{a}_{n}} \right\}\)的前\(n\)项的和为\({{S}_{n}}\),点\((n,{{S}_{n}})\)在函数\(f(x)=2{{x}^{2}}\)的图象上,数列\(\left\{ {{b}_{n}} \right\}\)满足:\({{b}_{1}}={{a}_{1}},{{b}_{n+1}}({{a}_{n+1}}-{{a}_{n}})={{b}_{n}}.\)其中\(n\in {{N}^{*}}\).

              \((\)Ⅰ\()\)求数列\(\left\{ {{a}_{n}} \right\}\)和\(\left\{ {{b}_{n}} \right\}\)的通项公式;

              \((\)Ⅱ\()\)设\({{c}_{n}}=\dfrac{{{a}_{n}}}{{{b}_{n}}}\),求证:数列\(\left\{ {{c}_{n}} \right\}\)的前\(n\)项的和\({{T}_{n}} > \dfrac{5}{9}(n\in {{N}^{*}}).\)

            • 6.

              设数列\(\left\{ {{a}_{n}} \right\}\)的前\(n\)项和为\({{S}_{n}}\),已知\(\dfrac{{{S}_{n}}}{2}={{a}_{n}}-{{2}^{n}} (\)\(n\)\(∈N*)\).

              \((1)\)求\({{a}_{1}}\)的值,若\({{a}_{n}}={{2}^{n}}{{c}_{n}}\),证明数列\(\{{{c}_{n}}\}\)是等差数列;

              \((2)\)设\({{b}_{n}}={{\log }_{2}}{{a}_{n}}-{{\log }_{2}}(n+1)\),数列\(\{\dfrac{1}{{{b}_{n}}}\}\)的前\(n\)项和为\({{B}_{n}}\),若存在整数\(m\),使对任意\(n\)\(∈\)\(N\)\(*\)且\(n\)\(\geqslant 2\),都有\({{B}_{3n}}-{{B}_{n}} > \dfrac{m}{20}\)成立,求\(m\)的最大值.

            • 7.
              已知等差数列\(\{a_{n}\}\)的前\(n\)项和为\(S_{n}\),\(S_{5}=35\),\(a_{5}\)和\(a_{7}\)的等差中项为\(13\).
              \((1)\)求\(a_{n}\)及\(S_{n}\);
              \((2)\)令\(b_{n}= \dfrac {1}{a_{n}^{2}-1}(n∈N^{*})\),求数列\(\{b_{n}\}\)的前项和\(T_{n}\).
            • 8.

              已知数列\(\{b_{n}\}\)是首项为\(2\)且公比为\(q\)的等比数列,数列\(\{a_{n}\}\)满足\(a_{1}=3q\),\(a_{n+1}-qb_{n+1}=a_{n}-qb_{n}(n∈N^{*}).\)

              \((1)\)求数列\(\{a_{n}\}\)的通项公式;

              \((2)\)若\(q= \dfrac{1}{2} \),数列\(\{b_{n}\}\)前\(n\)项和为\(S_{n}\),求所有满足等式\( \dfrac{{S}_{n}-m}{{S}_{n+1}-m}= \dfrac{1}{{b}_{m}+1} \)成立的正整数\(m\),\(n\);

              \((3)\)若\(q < 0\),且对任意\(m\),\(n∈N^{*}\),都有\( \dfrac{{a}_{m}}{{a}_{n}}∈\left( \dfrac{1}{6},6\right) \),求实数\(q\)的取值范围.

            • 9.

              已知等差数列\(\{a_{n}\}\)的前三项为\(a-1\),\(4\),\(2a\),记前\(n\)项和为\(S_{n}\),公差为\(d\)。

              \((\)Ⅰ\()\)设\(S_{k}=2550\),求\(a\)和\(k\)的值;

              \((\)Ⅱ\()\)设\({{b}_{n}}=\dfrac{{{d}^{{{a}_{n}}}}}{({{d}^{{{a}_{n+1}}}}-d)({{d}^{{{a}_{n+2}}}}-d)}\),求数列\(\{{{b}_{n}}\}\)的前\(n\)项和\({{T}_{n}}\).

            • 10.

              已知等比数列\(\{a_{n}\}\)的前\(n\)项和为\(S_{n}\),且\(a_{4}=2a_{5}\),\({S}_{6}= \dfrac{63}{64} \);

              \((1)\)求数列\(\{a_{n}\}\)的前\(n\)项和\(S_{n}\);

              \((2)\)设\({b}_{n}= \dfrac{{2}^{n}{a}_{n}}{{n}^{2}+n} \),求数列\(\{b_{n}\}\)的前\(n\)项和\(T_{n}\)

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