Goldbach's unproven conjecture claims that all even integers above 2 can be expressed as the sum of two primes.
What is the largest known number that can be written as a sum of two prime numbers in exactly two ways?
68 is the largest known number that can be written as a sum of two prime numbers in exactly two ways.
For more details refer to the article:
"Numbers that can be expressed as the (unordered) sum of two primes in exactly two ways"
inclusive of Sloane's Online Encyclopedia of Integer Sequences in this location:
https://oeis.org/A067188
Edited on November 10, 2022, 6:33 am
Puzzle Solution