# On the primality of n! +- 1 and 2 x 3 x 5 x ... x p +- 1

@article{Caldwell2002OnTP, title={On the primality of n! +- 1 and 2 x 3 x 5 x ... x p +- 1}, author={C. Caldwell and Y. Gallot}, journal={Math. Comput.}, year={2002}, volume={71}, pages={441-448} }

For each prime p, let p# be the product of the primes less than or equal to p. We have greatly extended the range for which the primality of n! ± 1 and p# ± 1 are known and have found two new primes of the first form (6380! + 1, 6917! - 1) and one of the second (42209# + 1). We supply heuristic estimates on the expected number of such primes and compare these estimates to the number actually found.

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