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Timeline for Binomial coefficient identity

Current License: CC BY-SA 3.0

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Nov 20, 2021 at 6:03 answer added qifeng618 timeline score: 1
Nov 20, 2017 at 10:06 comment added darij grinberg This has also recently appeared on math.stackexchange: math.stackexchange.com/questions/2455428/…
Dec 24, 2016 at 16:19 comment added T. Amdeberhan @hkju: I've posted a solution. I'm curious, what is the polytope you mentioned?
Dec 24, 2016 at 16:16 answer added T. Amdeberhan timeline score: 3
Dec 24, 2016 at 0:40 answer added KConrad timeline score: 1
Jan 11, 2015 at 6:11 comment added Ira Gessel This identity is also a special case of Vandermonde's theorem.
Jan 11, 2015 at 4:43 answer added KConrad timeline score: 11
Jan 11, 2015 at 4:06 answer added Todd Trimble timeline score: 9
Jan 11, 2015 at 1:53 answer added KConrad timeline score: 5
Jan 11, 2015 at 1:51 answer added Gjergji Zaimi timeline score: 9
Jan 11, 2015 at 0:10 answer added GH from MO timeline score: 10
Jan 10, 2015 at 22:19 comment added hkju This identity implies that $$ \sum_{k=0}^m \frac {n(-1)^k}{n+k} = \sum_{k=0}^n \frac {m(-1)^k}{m+k}$$.
Jan 10, 2015 at 22:01 history edited hkju CC BY-SA 3.0
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Jan 10, 2015 at 21:58 comment added hkju You mean, to reduce $\int_0^1 (1-x)^m x^{n-1} dx $ to $ \frac{m}{n} \int_0^1 (1-x)^{m-1} x^{n} dx $ using integration by parts, and so on..., right ?
Jan 10, 2015 at 16:52 answer added user64494 timeline score: -2
Jan 10, 2015 at 16:03 comment added darij grinberg Somewhat more elementary than the beta integral, whatever it is: use partial integration to reduce computing $\int_0^1 \left(1-x\right)^m x^{n-1} dx$ to computing $\int_0^1 \left(1-x\right)^{m+1} x^n dx$, and proceed by induction over $n$. This is purely algebraic.
Jan 10, 2015 at 15:32 review Close votes
Jan 11, 2015 at 18:56
Jan 10, 2015 at 15:14 comment added Lucia Look at $\int_0^1 (1-x)^m x^{n-1} dx$ and use the binomial theorem together with the beta integral.
Jan 10, 2015 at 15:11 history asked hkju CC BY-SA 3.0