Re: A prime number problem

Risto Kauppila <risto.kauppila0@xxxxxxxxxxxxxxxxxxxxxxxxxxxx> writes:
Let A = {2,3,13,23,37}
If (a_1,a_2,a_3,a_4,a_5)
is any permutation of A,
a_1 + a_2*a_3*a_4*a_5
a_1*a_2*a_3*a_4 + a_5
are all primes.
Can you find a set of six
or more primes satisfying
the same property.

A trickier one is to find sets s.t. for any subset, the product
of the subset plus the product of its complement is prime.

Unix is simple. It just takes a genius to understand its simplicity
-- Dennis Ritchie (1941-2011), Unix Co-Creator

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