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#c4d89245-52a2-48aa-bb36-db5a2a56d286简单解答题等差数列的概念与通项数列

14.在等差数列{an}\{a_{n}\}中满足,a3=16a_{3}=-16S9=72S_{9}=-72
(1)求等差数列{an}\{a_{n}\}的通项公式;
(2)若数列{an}\{a_{n}\}的前nn项的和为SnS_{n},判断SnS_{n}是否有最小值,若SnS_{n}有最小值,求此时nn的值;若SnS_{n}没有最小值,说明理由.