in Combinatory
128 views
1 vote
1 vote

Prove the hockeystick identity $\displaystyle{}\sum_{k=0}^{r} \binom{n + k}{k} = \binom{n + r + 1}{r}$ whenever $n$ and $r$ are positive integers,

  1.  using a combinatorial argument.
  2.  using Pascal’s identity.
in Combinatory
128 views

Please log in or register to answer this question.

Related questions