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Factorial creates prime (Posted on 2015-06-26)

a. The digits of N! can be rearranged to form a prime.
b. N>2

Find the smallest N, complying with the above statements.

No Solution Yet Submitted by Ady TZIDON

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Tricky Solution

Comment 5 of 5 |

8! = 40320

put the '0's together to make an '8'

now you have the digits 4,3,2, and 8

Several primes can be formed from these 4 digits, all ending in 3:

2843
4283
8243
8423

So the requested smallest N is 8.

Posted by Larry on 2020-05-19 11:54:42

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