题目

I learn English from Mr. Green every Saturday. (用now替换every Saturday改写句子)IEnglish from Mr. Green now. 答案:【1】am【2】learning16.已知向量$\overrightarrowhttp://pic.7249.cn$=(an,-2n),$\overrightarrow{q}$=(2n+1,an+1),n∈N*,向量$\overrightarrowhttp://pic.7249.cn$ 与$\overrightarrow{q}$ 垂直,且a1=1(1)求数列{an}的通项公式;(2)若数列{bn}满足bn=log2(an+1),求数列{an•bn}的前n项和Sn.
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