How do you simplify #2.5! #?

1 Answer

Using the Gamma function we have

#2.5! =Gamma(7/2)=5/2*Gamma(5/2)=5/2 *3/2*Gamma(3/2)= 5/2*3/2*1/2*Gamma(1/2) =\frac{15\sqrt \pi}8~~3.32335097045. #

For positive half-integers, the function values are given exactly by

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