720 is Product of Consecutive Numbers in Two Ways/Mistake
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Source Work
1997: David Wells: Curious and Interesting Numbers (2nd ed.):
- The Dictionary
- $720$
Mistake
- $10! = 7! \times 6!$, the only known example of a factorial being the product of two other factorials.
Correction
As is pointed out in Factorial as Product of Two Factorials, for all $n \in \Z_{>0}$:
- $\paren {n!}! = n! \paren {n! - 1}!$
So the above statement should be amended, for example as is done in the section on the number $10$, to say something like:
- Apart from the general rule ...
Sources
- 1997: David Wells: Curious and Interesting Numbers (2nd ed.) ... (previous) ... (next): $720$