25.已知数列{an}\{a_{n}\}{an}的通项公式为an=n+λn{a_n}=n+\frac{\lambda }{n}an=n+nλ,n∈N∗n\in N^{*}n∈N∗,且{an}\{a_{n}\}{an}为单调递增数列,则实数λ\lambdaλ的取值范围是 ___(−∞,2)(-\infty ,2)(−∞,2)___.