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- Mathematics the product of an integer and all the integers below it; e.g.factorial four (4!) is equal to 24. (Symbol: !)【数】阶乘, 析因（符号：!）。
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- the product of a series of factors in an arithmetical progression阶乘积, 因数乘积。
- chiefly Mathematics relating to a factor or such a product【主数】因子的; 阶乘的, 析因的：
a factorial design.
因子设计, 析因设计。
派生词