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**