is a2-4 prime
"is a2-4 prime"
Depends on the value of a.
If a = 3, then a2 - 4 = 5, which is prime.
If a = 4 then a2 - 4 = 12, which is not prime.
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Is a^2 - 4 prime?
If a is an integer > 3, it will be prime. Because if the least value to make it not prime = y, then
y - 2 > 1, because we can't let y-2 = 1.
y > 3.
If a is an integer < 3 it will be either prime or negative.