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My TI-83 calculator doesnt allow me to do this, but using Windows calculator, I can compute the factorial of say 5.8. What does this mean and how does it work?

Bill Dubuque
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Snowman
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    As I recall, these calculators can compute factorials of half-integers. But yes, you need $\Gamma(z)$ in general. – J. M. ain't a mathematician Nov 28 '10 at 01:29
  • Out of interest, what value do you get for $5.8!$? If it's based on the gamma function, you would get around $496.606\ldots$. (Everyone's mentioned the gamma function here, which is the most likely candidate, but there are other possible extensions of the factorial function to non-integers) – Chris Lewis Jul 06 '23 at 11:04

1 Answers1

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Perhaps you're looking for the Gamma function. It restricts to the usual factorial on natural numbers.

Wikipedia's article on Gamma function

Gigili
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