If x and (x² + 8) are both primes, then prove that (x³ +16) is also a prime.
(In reply to
Second thought by DJ)
I'm tempted to agree... I wrote a quick program (but it's late... and I may have made a mistake in it...), and I couldn't find any number that satisfies this... below 1,000,000 (apart from 3).
hmmmm
--- SK