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            • 1. 定义“规范\(01\)数列”\(\{a_{n}\}\)如下:\(\{a_{n}\}\)共有\(2m\)项,其中\(m\)项为\(0\),\(m\)项为\(1\),且对任意\(k\leqslant 2m\),\(a_{1}\),\(a_{2}\),\(…a_{k}\)中\(0\)的个数不少于\(1\)的个数\(.\)若\(m=4\),则不同的“规范\(01\)数列”共有\((\)   \()\)
              A.\(18\)个
              B.\(16\)个
              C.\(14\)个
              D.\(12\)个
            • 2. 已知等比数列\(\{a_{n}\}\)中,\(a_{2} > a_{3}=1\),则使不等式\((a_{1}- \dfrac {1}{a_{1}})+(a_{2}- \dfrac {1}{a_{2}})+(a_{3}- \dfrac {1}{a_{3}})+…+(a_{n}- \dfrac {1}{a_{n}})\geqslant 0\)成立的最大自然数\(n\)是 ______
            • 3.

              已知等差数列\(\left\{ {{a}_{n}} \right\}\)中公差\(d\ne 0\),有\({a}_{1}+{a}_{4}=14,且{a}_{1},{a}_{2},{a}_{7} \)成等比数列.

              \((\)Ⅰ\()\)求\(\left\{ {{a}_{n}} \right\}\)的通项公式\(a_{n}^{{}}\)与前\(n\)项和公式\({{S}_{n}}\);

              \((\)Ⅱ\()\)令\({{b}_{n}}=\dfrac{{{S}_{n}}}{n+k}\left( k\ne 0 \right)\),若\(\left\{ {{b}_{n}} \right\}\)是等差数列,求数列\(\left\{ \dfrac{1}{{{b}_{n}}{{b}_{n+1}}} \right\}\)的前\(n\)项和为\({{T}_{n}}\),

            • 4.

              如果一个数列从第\(2\)项起,每一项与它前一项的差都大于\(3\),则称这个数列为“\(S\)型数列” .

              \((1)\) 已知数列\(\{a_{n}\}\)满足\(a_{1}=4\),\(a_{2}=8\),\(a_{n}+a_{n-1}=8n-4(n\geqslant 2,n∈N^{*})\),求证:数列\(\{a_{n}\}\)是“\(S\)型数列”.

              \((2)\) 已知等比数列\(\{a_{n}\}\)的首项与公比\(q\)均为正整数,且\(\{a_{n}\}\)为“\(S\)型数列”,记\(b_{n}=\dfrac{3}{4}a_{n}\),当数列\(\{b_{n}\}\)不是“\(S\)型数列”时,求数列\(\{a_{n}\}\)的通项公式.

              \((3)\) 是否存在一个正项数列\(\{c_{n}\}\)是“\(S\)型数列”,当\(c_{2}= 9\),且对任意大于等于\(2\)的自然数\(n\)都满足\(\left( \dfrac{1}{n}\mathrm{{-}}\dfrac{1}{n{+}1} \right)\left( 2{+}\dfrac{1}{c_{n}} \right)\leqslant \dfrac{1}{c_{n\mathrm{{-}}1}}+\dfrac{1}{c_{n}}\leqslant \left( \dfrac{1}{n}\mathrm{{-}}\dfrac{1}{n{+}1} \right)\left( 2{+}\dfrac{1}{c_{n\mathrm{{-}}1}} \right)?\)如果存在,给出数列\(\{c_{n}\}\)的一个通项公式\((\)不必证明\();\)如果不存在,请说明理由.

            • 5.

              已知数列\(\{{{a}_{n}}\}\)满足:\({a}_{1}+{a}_{2}+{a}_{3}+...+{a}_{n}=n-{a}_{n} (n=1,2,3...)\)


              \((1)\)求证:数列\(\{a_{n}-1\}\)是等比数列;

              \((2)\)令\(b_{n}=(2-n)(a_{n}-1)(n=1,2,3...)\),如果对任意\(n∈N*\),都有\({b}_{n}+ \dfrac{1}{4}t\leqslant {t}^{2} \),求实数\(t\)的取值范围.

            • 6.

              已知\(\{a_{n}\}\)是等差数列,公差\(d\)不为零,前\(n\)项和是\(S_{n}\),若\(a_{3}\),\(a_{4}\),\(a_{8}\)成等比数列,则\((\)  \()\)

              A.\(a_{1}d > 0\),\(dS_{4} > 0\) 
              B.\(a_{1}d < 0\),\(dS_{4} < 0\) 
              C.\(a_{1}d > 0\),\(dS_{4} < 0\) 
              D.\(a_{1}d < 0\),\(dS_{4} > 0\)
            • 7.

              已知首项为\(\dfrac{3}{2}\)的等比数列\(\{{{a}_{n}}\}\)不是递减数列,其前\(n\)项和为\({{S}_{n}}(n\in {{N}_{+}})\),且\({{S}_{3}}+{{a}_{3}}\),\({{S}_{5}}+{{a}_{5}}\),\({{S}_{4}}+{{a}_{4}}\)成等差数列.

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

              \((2)\)设\({{T}_{n}}={{S}_{n}}-\dfrac{1}{{{S}_{n}}}(n\in {{N}_{+}})\),求数列\(\{{{T}_{n}}\}\)的最大项的值与最小项的值.

            • 8.

              已知\(\{a_{n}\}\)为等差数列,前\(n\)项和为\(S_{n}(n∈N^{*})\),\(\{b_{n}\}\)是首项为\(2\)的等比数列,且公比大于\(0\),\(b_{2}+b_{3}=12\),\(b_{3}=b_{4}-2a_{1}\),\(S_{11}=11b_{4}\).

              \((\)Ⅰ\()\)求\(\{a_{n}\}\)和\(\{b_{n}\}\)的通项公式;

              \((\)Ⅱ\()\)求数列\(\{a_{2n}b_{2n-1}\}\)的前\(n\)项和\((n∈N^{*}).\)

            • 9.

              设\(\{a_{n}\}\)是等差数列,\(\{b_{n}\}\)是各项为正数的等比数列,且\(a_{1}=1\),\(b_{1}=2\),\(a_{2+}b_{3\;}\) \(=11\), \(a_{3\;+}b_{5\;}\) \(=37\)

              \((1)\)求\(\{a_{n}\}\),\(\{b_{n}\}\)的通项公式;

              \((2)\)求数列\(\{ \dfrac{{a}_{n}}{{b}_{n}}\} \)的前\(n\)项和\(S_{n}\).

            • 10.

              若存在常数\(k(k∈{N}^{*} ,k\geqslant 2)\)、\(d\)、\(t\) \((d,t∈ R\) \()\),使得无穷数列\(\{an\}\)满足\({a}_{n+1}=\begin{cases}{a}_{n}+d, \dfrac{n}{k}∉{N}^{*}, \\ t{a}_{n,} \dfrac{n}{k}∈{N}^{*},\end{cases} \) 则称数列\(\{an\}\)为“段差比数列”,其中常数\(k\)、\(d\)、\(t\)分别叫做段长、段差、段比\(.\)设数列\(\{bn\}\)为“段差比数列”.

              \((1)\)已知\(\{bn\}\)的首项、段长、段差、段比分别为\(1\)、\(2\)、\(d\)、\(t.\)若\(\{bn\}\)是等比数列,求\(d\)、\(t\)的值;

              \((2)\)已知\(\{bn\}\)的首项、段长、段差、段比分别为\(1\)、\(3\)、\(3\)、\(1\),其前\(3n\)项和为\(S_{3n}.\)若不等式\({S}_{3n}\leqslant λ·{3}^{n-1} \)对\(n∈{N}^{*} \)恒成立,求实数\(λ \)的取值范围;

              \((3)\)是否存在首项为\(b\),段差为\(d(d\neq 0) \)的“段差比数列”\(\{b_{n}\}\),对任意正整数\(n\)都有\(b_{n+6}=b_{n}\),若存在,写出所有满足条件的\(\{bn\}\)的段长\(k\)和段比\(t\)组成的有序数组\((k,t)\);若不存在,说明理由.

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