Difference between revisions of "User:Borealbear"

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

Latest revision as of 18:22, 30 April 2021

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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?

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