Primality testing 26681^27074-27074^26681 [N-1/N+1, Brillhart-Lehmer-Selfridge]
Running N-1 test using base 3
Running N+1 test using discriminant 7, base 1+sqrt(7)
Calling N+1 BLS with factored part 0.01% and helper 0.00% (0.04% proof)
26681^27074-27074^26681 is Fermat and Lucas PRP! (503.8680s+0.0022s)

Sieved with xyyxsieve

To be completed...