Does there exist a prime number p such that both p3+2008 and p3+2010 are primes as well?
Solution
Let p be any prime number. If p is not divisible by 7, then p3 is congruent to either 1 or −1 modulo 7. Since 2008≡−1(mod7) and 2010≡1(mod7), either of the numbers p3+2008 and p3+2010 is divisible by 7 and hence composite. If p is divisible by 7, then p=7 and p3+2010=73+2010=2353=13⋅181 is composite, too.
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Source: MathNet,
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