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            • 1.

              已知数列\(\left\{ {{a}_{n}} \right\}\)满足\({{a}_{2}}=102,{{a}_{n+1}}-{{a}_{n}}=4n,\) \(\left( n\in {{N}^{*}} \right)\),则数列\(\left\{ \dfrac{{{a}_{n}}}{n} \right\}\)的最小值是\((\)   \()\)

              A.\(25\)   
              B.\(26\)   
              C.\(27\)   
              D.\(28\)
            • 2.

              将正整数按下表排列:则\(101\)在(    )

              第\(1\)列

              第\(2\)列

              第\(3\)列

              第\(4\)列

              第\(1\)行

              \(1\)

              \(2\)

              \(3\)

              \(4\)

              第\(2\)行

              \(7\)

              \(6\)

              \(5\)

              第\(3\)行

              \(9\)

              \(10\)

              \(11\)

              \(12\)

              第\(4\)行

              \(16\)

              \(15\)

              \(14\)

              \(13\)

              \({…}\)

              \({…}\)

              \({…}\)

              \({…}\)

              \({…}\)

              A.第\(25\)行,第\(1\)列            
              B.第\(25\)行,第\(4\)列
              C.第\(26\)行,第\(1\)列             
              D.第\(26\)行,第\(4\)列
            • 3.

              已知\(a_{n+1}-a_{n}-3=0\),则数列\(\{a_{n}\}\)是\((\)  \()\)

              A.递增数列                 
              B.递减数列

              C.常数列                                    
              D.摆动数列
            • 4.

              数列\(\{{{a}_{n}}\}\)满足\({{a}_{1}}=1,n{{a}_{n{+}1}}=(n+1){{a}_{n}}+n(n+1)\),且\({{b}_{n}}={{a}_{n}}\cos \dfrac{2n\pi }{3}\),记\({{S}_{n}}\)为数列\(\{{{b}_{n}}\}\)的前\(n\)项和,则\({{S}_{24}}=\)

              A.\(294\)
              B.\(174\)
              C.\(470\)
              D.\(304\)
            • 5.

              已知函数\(f(x)=\dfrac{3x}{ax+b}\),\(f(1)=1\),\(f(\dfrac{1}{2})=\dfrac{3}{4}\),数列\(\{x_{n})\)满足\({{x}_{1}}=\dfrac{3}{2}\),\(x_{n+1}=f(x_{n}).\)

              \((1)\)求\(x_{2}\),\(x_{3}\)的值;

              \((2)\)求数列\(\{x_{n}\}\)的项公式;

              \((3)\)证明:\(\dfrac{{{x}_{1}}}{3}+\dfrac{{{x}_{2}}}{{{3}^{2}}}+...+\dfrac{{{x}_{n}}}{{{3}^{n}}} < \dfrac{3}{4}\).

            • 6. 在数列\(\{a_{n}\}\)中,\(a_{n}=-2n^{2}+29n+3\),则此数列最大项的值是\((\)  \()\)
              A.\(102\)
              B.\( \dfrac {865}{8}\)
              C.\( \dfrac {817}{8}\)
              D.\(108\)
            • 7.

              已知数列\(\{a_{n}\}\)的各项均为正整数,其前\(n\)项和为\(S_{n}\),若\(a_{n+1}=\begin{cases} \dfrac{a_{n}}{2},a_{n}是偶数 \\ 3a_{n}+1,a_{n}是奇数 \end{cases}\),且\(a_{1}=5\),则\(S_{2\;018}=(\)  \()\)

              A.\(4 740\)                                                
              B.\(4 732\)

              C.\(12 095\)                                               
              D.\(12 002\)
            • 8.

              已知函数\(f\left( x \right)=\begin{cases} {{a}^{x-5}},x\geqslant 6, \\ \left( 4-\dfrac{a}{2} \right)x+4,x < 6, \end{cases}\)数列\(\left\{{a}_{n}\right\} \)满足\({{a}_{n}}=f\left( n \right)\left( n\in {{N}^{*}} \right)\),且数列\(\left\{{a}_{n}\right\} \)是递增数列,则实数\(a\)的取值范围是______.

            • 9.

              设等差数列\(\{a_{n}\}\)满足\(a_{2}=7\),\(a_{4}=3\),\(S_{n}\)是数列\(\{a_{n}\}\)的前\(n\)项和,则使得\(S_{n} > 0\)成立的最大的自然数\(n\)是(    )

              A.\(9\)
              B.\(10\)
              C.\(11\)
              D.\(12\)
            • 10.
              已知数列\(\{a_{n}\}\)中,\(a_{1}= \dfrac {3}{5},a_{n}=2- \dfrac {1}{a_{n-1}}(n\geqslant 2,n\in N*)\),数列\(\{b_{n}\}\)满足\(b_{n}= \dfrac {1}{a_{n}-1}(n\in N*)\).
              \((1)\)求证:数列\(\{b_{n}\}\)是等差数列;
              \((2)\)求数列\(\{a_{n}\}\)中的最大项和最小项,并说明理由.
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