If the lengths of the sides of a triangle are consecutive integers could the perimter be a prime number?
The only even prime number is 2, and that can't be the perimeter of a triangle
with consecutive integer sides, so the perimeter must be odd in order to be a
prime number. So we cannot have the shortest side odd, the middle sized side
even, and the largest side odd, since the perimeter would then be even,
since "odd+even+odd=even"
So the shortest side must be even, the medium-size side must be odd, and
the longest side must be even, and that works since even+odd+even=odd.
So let the shortest side be 2n where n is any integer,
So the sides are 2n, 2n+1, and 2n+2. That makes the perimeter be:
2n + (2n+1) + (2n+2)
So perimeter = 2n + 2n + 1 + 2n + 2
Perimeter = 6n + 3
Perimeter = 3(2n+1)
So the perimeter is always divisible by 3 so it cannot be prime.
The answer is NO.
Edwin