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            • 1.

              已知数列\(\left\{ {{a}_{n}} \right\}\)的通项公式为\({a}_{n}={n}^{2}-2λn+1\left(n∈{N}^{*}\right) \),且数列\(\left\{ {{a}_{n}} \right\}\)为递增数列”,则\(\lambda \)的取值范围是_______________.

            • 2.

              已知数列\(\{{{a}_{n}}\}\)的前\(n\)项和为\({{S}_{n}}\),点\(\left( n,{{S}_{n}} \right)\)在函数\(f(x)={{x}^{2}}-2kx(k\in N)\)图象上,当且仅当\(n=4\)时,\({{S}_{n}}\)的值最小.

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

              \((\)Ⅱ\()\)令\({{c}_{n}}=\dfrac{{{a}_{n}}+9}{2}\),数列\(\{{{b}_{n}}\}\)满足\({{b}_{n}}=\dfrac{{{2}^{{{c}_{n}}}}}{({{2}^{{{c}_{n}}}}-1)({{2}^{{{c}_{n+1}}}}-1)}\),记数列\(\{{{b}_{n}}\}\)的前\(n\)项和为\({{T}_{n}}\),若\(2{{m}^{2}}-3m+\dfrac{5}{3}-{{T}_{n}}\leqslant 0\)恒成立,求实数\(m\)的取值范围.

            • 3.

              若正项数列\(\{a_{n}\}\)的前\(n\)项和为\(S_{n}\),首项\(a_{1}=1\),\(P\left( \sqrt{{{S}_{n}}},{{S}_{n+1}} \right)\)点在曲线\(y=(x+1)^{2}\)上\(.\)

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

              \((2)\)设\({{b}_{n}}=\dfrac{1}{{{a}_{v}}\cdot {{a}_{n+1}}}\),\(T_{n}\)表示数列\(\{b_{n}\}\)的\(n\)项和,若\(T_{n}\geqslant a\)恒成立,求\(T_{n}\)及实数\(a\)的取值范围.

            • 4.
              已知数列\(\{a_{n}\}\)的前\(n\)项和\(S_{n}=n^{2}+1(n∈N^{*})\),则它的通项公式是 ______ .
            • 5.

              定义:称\( \dfrac{n}{{p}_{1}+{p}_{2}+⋯{P}_{n}} \)为\(n\)个正数\(p_{1}\),\(p_{2}\),\(…\),\(p_{n}\)的“均倒数”,若数列\(\{a_{n}\}\)的前\(n\)项的“均倒数”为\( \dfrac{1}{2n+1} \),则数列\(\{a_{n}\}\)的通项公式为     

            • 6.

              已知等差数列\(\{a_{n}\}\)的首项为\(a\),公差为\(b\);等比数列\(\{b_{n}\}\)的首项为\(b\),公比为\(a\),其中\(a\),\(b\)均为正整数,且\(a_{1} < b_{1} < a_{2} < b_{2} < a_{3}\).

              \((I)\)求\(a\)的值;

              \((\)Ⅱ\()\)若对于\(\{a_{n}\}\),\(\{b_{n}\}\),存在\(m\),\(n∈N^{*}\),满足\(a_{m}+1=b_{n}\),求\(b\)的值;

              \((\)Ⅲ\()\)对于满足\((\)Ⅱ\()\)的数列\(\{a_{n}\}\),\(\{b_{n}\}\),令\({{c}_{n}}=\dfrac{{{a}_{n}}-8}{{{b}_{n}}}\),求数列\(\{c_{n}\}\)的最大项.

            • 7.
              已知等比数列\(\{a_{n}\}\)的公比\(q > 1\),\(a_{1}=2\),且\(a_{1}\),\(a_{2}\),\(a_{3}-8\)成等差数列,数列\(\{a_{n}b_{n}\}\)的前\(n\)项和为 .

              \((1)\)分别求出数列\(\{a_{n}\}\)和\(\{b_{n}\}\)的通项公式;

              \((2)\)设数列 ,\(V_{n}∈N^{*}\),\(c_{n}\leqslant m\)恒成立,求实数\(m\)的最小值.

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