Bifalgorithm post · Brisk · Chapter 1
When are the numbers of combinations greatest and smallest?
When are the numbers of combinations greatest and smallest? (Brisk · Chapter 1) — "Also notice that the way to get the greatest number of combinations of n ite…
Ideas in this flowchart
- Number of combinations of n items when choosing k
- The greatest number of combinations occurs when k is half of n
- Example: choosing books from a library
- With 100 books, choosing 50 gives more combinations than choosing 5 or 95
- Extreme endpoints always produce exactly one combination
- Choosing no items: (n 0) = 1
- There is only one way to choose nothing: come up empty
- Choosing all items: (n n) = 1
- There is only one way to choose everything: pick all the items
