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#33f901b7-f954-4f99-b58e-cc2e2afc5ba7中等解答题数列求和方法数列

26.(2023•湖南模拟)记SnS_{n}为数列{an}\{a_{n}\}的前nn项和,已知a1=1,Snan+1Snan=12{a_1}=1,\frac{S_n}{a_{n+1}}-\frac{S_n}{a_n}=-\frac{1}{2}
(1)求{an}\{a_{n}\}的通项公式;
(2)令bn=2an{b_n}={2^{a_n}},记数列{bn}\{b_{n}\}的前nn项和为TnT_{n},试求T2n1T_{2n-1}除以3的余数.