For a and b being integers, when the result of the expression above is an integer, and n is not equal to a + b, I perdict that:
- n is prime;
- n isn't 2.
Can you prove or counter my prediction?
(a, b, n having different names implies that they have different values)
a = 6, b = 3, n = 9 results in 61965
9 is not prime.
So you did. However
a = 6, b = 3, n = 27 results in 2105947230095214567
You still need to tighten your constraints!