How this calculation works
Enumerate prime pairs that add to the given even integer.
THE FORMULA
List primes p ≤ n/2 for which n−p is also primeA worked example
28 can be written as 5+23 and 11+17.
Good to know
This checks one integer and reports each pair once.
Reference: NIST DLMF, Functions of Number Theory (opens in a new tab) ↗
Read the result
Enumerate prime pairs that add to the given even integer.
The primary result is labeled “Unordered prime pairs”. Keep the input definitions in view when comparing this result with another method.
Try a related calculation
This checks one integer and reports each pair once.
For a related exercise, try the greatest common divisor.
A few questions, answered
How can I check the default inputs by hand?
28 can be written as 5+23 and 11+17.
Which rule does this calculator apply?
List primes p ≤ n/2 for which n−p is also prime