关于前段时间所谓“韦神”出的“难题”

2023-04-01 12:20 作者:げいしも_芸 0人读过 | 我要投稿

先看题

我们直接开始解答

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而

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$%3D2%5Csum_%7Bk%3D0%7D%5E%7B%2B%5Cinfty%7D%5Csum_%7B1%5Cleq%20i%2Cj%5Cleq%20n%7D%5Cfrac%7B(a_ia_j)%5E%7B2k%2B1%7D%7D%7B2k%2B1%7D$

$%3D%5Csum_%7Bk%3D0%7D%5E%7B%2B%5Cinfty%7D%5Cleft(%5Cfrac%7B2%7D%7B2k%2B1%7D%5Csum_%7Bi%3D1%7D%5Ena_i%5E%7B2k%2B1%7D%5Csum_%7Bj%3D1%7D%5Ena_j%5E%7B2k%2B1%7D%5Cright)$