Difference of Squares of Odd Primes Modulus 24

If  
\[p \gt 5\]
  is a prime number.  
\[gcd(p,12)\]
  must be equal to 1, so  
\[p \equiv 1, \; 5, \; 7, \; 11 \; (mod \; 12)\]
. If  
\[q \gt p \gt 5\]
  is also prime then  
\[q \equiv 1, \; 5, \; 7, \; 11 \; (mod \; 12)\]
  too.
\[1^2=1, \; 5^2=25, \; 7^2=49, \; 11^2=121\]

The difference between any two of these is a multiple of 24, so  
\[q^2-p^2 \equiv 0 \; (mod \; 24)\]
.

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