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Announcements
QOJ 更新日志 by Qingyu 2023-01-06 20:27:29
Petrozavodsk Summer 2021 Announcement by QOJ_News 2021-07-30 15:33:46
XXII Open Cup 新闻合集 / 比赛列表合集 by Qingyu 2021-09-02 23:08:35
XXI Open Cup 新闻合集 by Qingyu 2020-09-29 15:47:48
 
 
 
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#UsernameMottoSolved
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1larryzhong698
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3HuangHanSheng324
4MaMengQi323
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7hyddQingyu txdy! | Who will guard the guardians? | Solve more problems. | 警惕境外势力入侵qoj254
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8Wu_Ren187
9repoman$$\prod_{i=0}^{n-1} (1+q^iz) = \sum_{i=0}^n q^{i(i-1)/2}\binom ni_q z^i$$174
10Lenstarorz Qingyu157
11Crysfly$$f(x)=(\sum_{i=0}^{n-1}\frac{y_i}{(x-q^i)\prod_{j\ne i}(q^i-q^j)})\prod_{i=0}^{n-1}(x-q^i)$$ 150
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19hutality$$[x^n](1-x)^{-\frac{1}{2}} \exp\left(\frac{x(1+x)}{2-2x}\right)\frac{\left(\frac{2-x}{2-2x}\right)^k}{k!}\cdot\,_0 F _1 \left(;k+1;x\left(\frac{2-x}{2-2x}\right)^2\right)$$112
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