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#2ef27031-adc2-4d28-ad61-259f81505e15中等解答题数列求和方法数列

1. 已知等差数列{an}\{a_{n}\}满足a2=4a_{2}=42a4a5=72a_{4}-a_{5}=7,公比不为1-1的等比数列{bn}\{b_{n}\}满足b3=4b_{3}=4b4+b5=8(b1+b2)b_{4}+b_{5}=8(b_{1}+b_{2})
(1)求{an}\{a_{n}\}{bn}\{b_{n}\}的通项公式;
(2)设cn=anbnc_{n}=a_{n}b_{n},求{cn}\{c_{n}\}的前nn项和SnS_{n}