Revision as of 16:23, 22 April 2021 by Borealbear (talk | contribs)


Congrats on finding this page! Here's a problem I made: Suppose a positive integer with all digits non-zero is considered [i]almost unique[/i] if there are fewer than $5$ permutations of its digits. For example, $122$ is [i]almost unique[/i] since it has $3$ permutations,($122$, $212$, and $221$), while $123$ is not since it has $6$ permutations, ($123$, $132$, $213$, $231$, $312$, $321$). How many [i]almost unique[/i] numbers less than $1000000$ are there?

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