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Problem 41

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Pandigital Prime

We shall say that an $n$-digit number is pandigital if it makes use of all the digits $1$ to $n$ exactly once. For example, $2143$ is a $4$-digit pandigital and is also prime.

What is the largest $n$-digit pandigital prime that exists?

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全数字素数

如果一个$n$位数恰好使用了$1$至$n$每个数字各一次，则称为全数字数。例如，$2143$就是一个$4$位全数字数，同时它也是一个素数。

最大的全数字素数是多少？

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