9.
如果无穷数列\(\{{{a}_{n}}\}\)满足下列条件:\(①\dfrac{{{a}_{n}}+{{a}_{n+2}}}{2}\leqslant {{a}_{n+1}}\);\(②\)存在实数\(M\),使得\({{a}_{n}}\leqslant M\),其中\(n\in {{N}^{*}}\),那么我们称数列\(\{{{a}_{n}}\}\)为\(\Omega \)数列.
\((1)\)设数列\(\{{{b}_{n}}\}\)的通项为\({{b}_{n}}=5n-{{2}^{n}}\),且是\(\Omega \)数列,求\(M\)的取值范围;
\((2)\)设\(\{{{c}_{n}}\}\)是各项为正数的等比数列,\({{S}_{n}}\)是其前\(n\)项和,\({{c}_{3}}=\dfrac{1}{4},{{S}_{3}}=\dfrac{7}{4}\),证明:数列\(\{{{S}_{n}}\}\)是\(\Omega \)数列;
\((3)\)设数列\(\{{{d}_{n}}\}\)是各项均为正整数的\(\Omega \)数列,求证:\({{d}_{n}}\leqslant {{d}_{n+1}}\).