Primality testing 26372^28057-28057^26372 [N-1/N+1, Brillhart-Lehmer-Selfridge]
Running N-1 test using base 3
Running N-1 test using base 7
Running N-1 test using base 11
Running N+1 test using discriminant 23, base 2+sqrt(23)
Calling N+1 BLS with factored part 0.01% and helper 0.00% (0.04% proof)
26372^28057-28057^26372 is Fermat and Lucas PRP! (1731.7594s+0.0036s)

Sieved with xyyxsieve

To be completed...