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#60493610-67db-4a1c-bfdb-28bfbcb96352简单解答题等差数列的概念与通项数列

22.已知等差数列{an}\{a_{n}\}的前nn项和为SnS_{n}Sm1=16S_{m-1}=16Sm=25S_{m}=25Sm+2=49(m2,mN){S}_{m+2}=49(m\geqslant 2,m\in {N}^{*}),则实数mm的值是 [ 5 ].