7.4: Summary
( \newcommand{\kernel}{\mathrm{null}\,}\)
- If n>0 is an integer, then
\binom{−n}{r} = (−1)^r \binom{n + r − 1}{r}.
- The Generalised Binomial Theorem
- 1 + x + . . . + x^k = \dfrac{(1 − x^{k+1})}{(1 − x)}
- Using generating functions for counting things
- Important Definitions:
- Generating function for a sequence
- Generalised binomial coefficient