Problems & Puzzles: Puzzles

Puzzle 465. Factorials

Farideh sent the following nice puzzle:


Q. What is the next prime (see


On Dec 08 Qu, Shun Liang wrote:

I have search up to 2*10^14, and find none of them.

I found 209210612202, 209210612212, 209210612220, 209210612221, ( A066457 )

But unfortunately,all of them are composite number. I think there will be a number in 10^18, but it too hard to reach. A discussion about this problem:





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