Skip to main content

All Questions

Filter by
Sorted by
Tagged with
6 votes
3 answers
1k views

Is there a generalization (surely there is) of this simple combinatorial identity?

I was just doing some algebra on a paper and obtained: $$\sum_{l=0}^{n-1} {{n+l} \choose l}={2n \choose {n+1}}$$ Are there some generalizations of this identity? One possible generalization would be ...
Shalom's user avatar
  • 513