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#350de54f-fad8-4ec8-833d-1bd90faeafac简单fill_compute数列求和方法数列

24.数列{an}\{a_{n}\}满足tanan=1n2+n+1\tan {a}_{n}=\frac{1}{{n}^{2}+n+1}an(0,π2){a}_{n}\in (0,\frac{\pi }{2})SnS_{n}{an}\{a_{n}\}的前nn项和,若Sn<kS_{n}<k,则kk的范围为 ___[π4,+)[\frac{\pi }{4},+\infty )___.