Problems & Puzzles: Problems

Problem 52.  p 2^n

F. Cohen and J. L. Selfridge observed in 1975 that 47867742232066880047611079 is a prime number such that plus or minus a power of 2 can never be prime.

 

Q1. Can you find a smaller solution?

Q2. Just take p+2^n and get champions of this type

 

 




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