2021 AMC 10A Problems/Problem 20
Revision as of 16:08, 11 February 2021 by Contactbibliophile (talk | contribs)
Problem
In how many ways can the sequence be rearranged so that no three consecutive terms are increasing and no three consecutive terms are decreasing?
Solution (bashing)
We write out the 120 cases.
[hide=The Cases]
[/hide]
Some quick work gets us
permutations that work. ~contactbibliophile