Hockey-stick identity | general mathematics | intermediate level

Episode 128.

Hockey-stick identity | general mathematics | intermediate level.

Branch of mathematics: general mathematics.
Difficulty level: intermediate.

Theorem (the hockey-stick identity). For any $k$, $n$, such that $k \leq n$, we have $\sum_{j=k}^{n}{\binom{j}{k}}=\binom{n+1}{k+1}$.

Mathematics.
#Mathematics

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