Factorial Primes: Middle Secondary Mathematics Competitions

A factorial prime is a prime number of the form p = n! + 1 or p = n! – 1, where n is a positive integer.

Find the sum of all such distinct factorial primes under 50.

As always, show your solution. Add your answer to the Comments below.

In a competition, without any electronic devices, this question should take about 2 minutes.


Level: Middle Secondary (Yellow)



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