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#4f57ca1c-235e-4f47-9382-7d34dbcb441f基础填空题数列求和方法数列

13.已知数列{an}\{a_{n}\}的前nn项和为SnS_{n},且满足an={2n1,n=2k1,kN5n+1,n=2k,kN{a}_{n}=\left\{\begin{array}{l}2n-1,&n=2k-1,k\in {N}^{*}\\ 5n+1,&n=2k,k\in {N}^{*}\end{array}\right.,则S10=(S_{10}=(  ))