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A comment on Decomposing a Factorial into Large Factors.

Re:Decomposing a Factorial into Large Factors by dvh on Friday March 28, 2025 @02:20PM (#43508490)
As a kid I was bugged by the fact that Stirling formula doesn't give exact integer result, so I set to find my own formula. I failed, but discovered that sum from 1 to N is (n*n+n)/2. Surely if perfect formula for sum exists, for multiplication should exist too.
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Re:Decomposing a Factorial into Large Factors by HeliumHydride on Friday March 28, 2025 @02:25PM (#43508548)
https://en.wikipedia.org/wiki/Gamma_function
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Re:Decomposing a Factorial into Large Factors by xinu2020 on Friday March 28, 2025 @02:39PM (#43508665)
For those who are curious how we can construct such a function, and why it looks so funky on the negative side, I strongly recommend this video https://www.youtube.com/watch?v=v_HeaeUUOnc
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Re:Decomposing a Factorial into Large Factors by zamadatix on Friday March 28, 2025 @06:42PM (#43510659)
I think they mean a (traditionally) closed form expression, for which I don't know if there is a particularly simple explanation of why there isn't such a form but there is for summing integers to n instead of multiplying them.
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