3.
已知单调递增的等比数列\(\{a_{n}\}\)满足:\(a_{2}+a_{3}+a_{4}=28\),且\(a_{3}+2\)是\(a_{2}\),\(a_{4}\)的等差中项.
\((\)Ⅰ\()\)求数列\(\{a_{n}\}\)的通项公式;
\((\)Ⅱ\()\)若\(b_{n}=a_{n}\log \;_{ \frac {1}{2}}a_{n}\),\(S_{n}=b_{1}+b_{2}+b_{3}+…+b_{n}\),对任意正整数\(n\),\(S_{n}+(n+m)a_{n+1} < 0\)恒成立,试求\(m\)的取值范围.