Revision as of 16:26, 22 April 2021 by Borealbear (talk | contribs)


Congrats on finding this page! Here's a problem I made: $\newline$

Suppose a positive integer with all digits non-zero is considered $\textit{almost unique}$ if there are fewer than $5$ permutations of its digits. For example, $122$ is $\textit{almost unique}$ since it has $3$ permutations,($122$, $212$, and $221$), while $123$ is not since it has $6$ permutations, ($123$, $132$, $213$, $231$, $312$, and $321$). How many $\textit{almost unique}$ numbers less than $1000000$ are there?

Invalid username
Login to AoPS