Simplifying a sum of factorials (1 Viewer)

[BenHowe]

How do I simplify

Not sure if this is ext 2, just doing an applied maths problem

 

[KingOfActing]

How do I simplify

Not sure if this is ext 2, just doing an applied maths problem

There's no easy way to simplify that unless you're willing to use hypergeometric/subfactorial/etc. functions.

WolframAlpha gives:

 

[Paradoxica]

How do I simplify

Not sure if this is ext 2, just doing an applied maths problem

Let the sum be X

Observe nX = n! + X -1

Then solve for X

 

[BenHowe]

That's very clever lol. So for stuff like this I have to find how I can re-write the expression to a more useful form/express it in terms of itself?

 

[stupid_girl]

Let the sum be X

Observe nX = n! + X -1

Then solve for X

I don't think it works.
This is not a GS.
nX = n! + n (n-2)! + n (n-3)! + ......

 

[Paradoxica]

I don't think it works.
This is not a GS.
nX = n! + n (n-2)! + n (n-3)! + ......

whoops XD

should have picked up on that immediately...

Time to induct