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#07d0a5db-0f94-4482-bf71-9f446e9bb013简单解答题数列求和方法数列

15.(2023•哈尔滨二模)已知数列{an}\{a_{n}\}的首项a1=35{a_1}=\frac{3}{5},且满足an+1=3an2an+1{a_{n+1}}=\frac{3{a_n}}{2{a_n}+1}
(1)求证:数列{1an1}\left\{{\frac{1}{a_n}-1}\right\}为等比数列;
(2)设数列{bn}\{b_{n}\}满足求最小的实数mm,使得b1+b2++b2k<mb_{1}+b_{2}+\ldots +b_{2k}<m对一切正整数kk均成立.