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#fa52733d-6f11-4199-9e8d-896dbff882ea简单解答题数列求和方法数列

14. 已知数列{an}\{a_{n}\}为递增的等差数列,SnS_{n}{an}\{a_{n}\}的前nn项和,a1+a5=18a_{1}+a_{5}=18a2a4=65a_{2}a_{4}=65bn=Snn+c{b_n}=\frac{S_n}{n+c}
(1)若数列{bn}\{b_{n}\}为等差数列,求非零常数cc的值;
(2)在(1)的条件下,cn=bn+12n{c_n}=\frac{{b_n}+1}{2^n},求{cn}\{c_{n}\}的前nn项和TnT_{n}