Does the definition of factorial fail for $0!$
2959
Prove $0! = 1$ from first principles
14150
Zero to the zero power – is $0^0=1$?
10313
Why Multiplication of zero by any number is zero?
145582
$\sum (-1)^n/n$ fails the p-series test, but passes the alternating series test?
43499
Repeatedly taking differences on a polynomial yields the factorial of its degree?
20611
Inverse of a factorial
109131
Find limit with factorial
93944
How to calculate what this power series converges against? (double factorials)
61673
Could I define 0^0 to be 1?
118571
Why is $\sum\limits_{k=0}^{n}(-1)^k\binom{n}{k}^2=(-1)^{n/2}\binom{n}{n/2}$ if $n$ is even?
107686
Proof that the gamma function is an extension of the factorial function
50688
Integrating Factor Method. Why Can We Set the Constant of Integration to Zero?
158335
Why is this $0 = 1$ proof wrong?
62163
How to find the factorial of a fraction?
31954
Why this proof $0=1$ is wrong?(breakfast joke)
81561
Limit of factorial function: $\lim\limits_{n\to\infty}\frac{n^n}{n!}.$
113684
Does series with factorials converge/diverge: $\sum\limits_{n=1}^\infty \frac{4^n n!n!}{(2n)!}$?