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#72fb0f56-6418-400c-810f-c8ba951dfdf2简单解答题等差数列的概念与通项数列

25.已知等差数列{an}\{a_{n}\}的前nn项和为SnS_{n},若S15S10=1S_{15}-S_{10}=1,则S25=S_{25}=[ 5 ].