---

Problem 118

---

Pandigital prime sets

Using all of the digits 1 through 9 and concatenating them freely to form decimal integers, different sets can be formed. Interestingly with the set {2,5,47,89,631}, all of the elements belonging to it are prime.

How many distinct sets containing each of the digits one through nine exactly once contain only prime elements?

---

全数字素数集合

使用1至9的全部数字，并自由连接起来组成十进制整数，可以构造不同的集合。其中一个集合{2,5,47,89,631}非常有趣，因为它的所有元素都是素数。

有些集合包含数字1至9恰好各一次，且所有元素都是素数，这样的集合有多少个？

---