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Timeline for Finite sum of reciprocal factorials

Current License: CC BY-SA 4.0

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Mar 21, 2019 at 15:02 vote accept slomil
Mar 20, 2019 at 23:44 answer added Robert Israel timeline score: 0
Mar 20, 2019 at 23:33 comment added Daniel Schepler It looks like a convolution of $\frac{1}{k}$ with $\frac{1}{k!}$ - so its generating function would probably be something like $e^x \cdot (-\ln(1-x))$.
Mar 20, 2019 at 23:24 comment added Sidharth Ghoshal Maybe try sticking an $x^k$ to it each term. Then it becomes some polynomial. If you differentiate this polynomial it takes on the form. $$ \frac{1}{(n-1)!} + \frac{1}{(n-2)!}x + ...$$ but it’s not clear if this direction is fruitful.
Mar 20, 2019 at 23:23 comment added Arthur Are you certain that it's $k$ in the denominator and not $k!$? (That's a factorial and a question mark, not an interrobang.)
Mar 20, 2019 at 23:23 history edited Sidharth Ghoshal
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Mar 20, 2019 at 23:22 comment added PrincessEev Hm. With the multiplication by $n!$, each summand has the form $$\binom n k \cdot (k-1)!$$ I wonder if that means anything.
Mar 20, 2019 at 23:21 history edited slomil CC BY-SA 4.0
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Mar 20, 2019 at 23:20 review First posts
Mar 20, 2019 at 23:27
Mar 20, 2019 at 23:15 history asked slomil CC BY-SA 4.0