Descending digit sequences
Julia, 30 bytes



n-&gt;"$n"join(n-1:-1:0)[1:n]"$n"


This is an anonymous function that accepts an integer and returns a string. To call it, assign it to a variable.

We construct and join the descending sequence from n-1 to 0, and take the first n characters from the resulting string. We prepend and append this with the input as a string.

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