名詞 factorial:

1. the product of all the integers up to and including a given integer

形容詞 factorial:

1. of or relating to factorials

fac.to.ri.al

n.（名詞）
The product of all the positive integers from to a given number:
階乘：從到所給數(shù)字中的所有正數(shù)相乘：
例句：
4 factorial, usually written 4!, is equal to 24 ( × 2 × 3 × 4 = 24).
4的階乘，常寫作4！，等于24（×2×3×4＝24）

adj.（形容詞）
Of or relating to a factor or factorial.
因數(shù)或階乘的：因數(shù)或階乘的，與因數(shù)或階乘有關(guān)的