About fact2(n)

[-MFra-]

Hi,

does fact2 (n) not work? or, isn't correct, the use I make of it?

[AlanStevens]

Works for me in M15:

If I try   fact2(10)=    I get the error message "This variable is not defined".  (It's symbolic only)

Alan

[-MFra-]

I also use M15.

[LucMeekes]

Appears to be wrong, see also:https://www.maplesoft.com/support/help/Maple/view.aspx?path=factorial

Success!
Luc

[-MFra-]

I have the impression that you are making confusion. The double factorial is not the factorial of the factorial of n. On Wiki ... there is a broad description.

[StuartBruff · Accepted solution]

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@-MFra- wrote:

I have the impression that you are making confusion. The double factorial is not the factorial of the factorial of n. On Wiki ... there is a broad description.

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The number that you show fact2(3) evaluating to is actually (4!)! (620448401733239000000000).   (10!)! is monstrously long.

Do you have anything else defined earlier in your worksheet that might affect the result?

Cheers,

Stuart

[-MFra-]

there must be interference with something defined in a large reference file, which I am using. In fact, if I use fact2 in a new file without a reference file, everything is fine.

[-MFra-]

I found the problem. In the definition of the new operator !!,  there was a redefinition of fact2.

Thank you