Prove that $\binom{n}{r}$ is always an integer for all $n$ and for $0 ≤ r ≤ n$.
Asked
Active
Viewed 74 times
0
-
1Possible to refer to this thread: https://math.stackexchange.com/questions/11601/proof-that-a-combination-is-an-integer – Icycarus Jun 04 '17 at 16:11
-
Since $\binom{n-1}r$ and $\binom{n-1}{r-1}$ are integers, $\binom nr$ is an integer if $0<r<n$. – peterwhy Jun 04 '17 at 16:13