Exclamation mark

1. Feb 24, 2009

peaceandlove

What does the exclamation mark mean in calculus? For example, a question might ask for the sum of a series ((-1)^n)/n!.

2. Feb 24, 2009

Staff: Mentor

In many math applications, it refers to the factorial:

http://en.wikipedia.org/wiki/Factorial

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