Primality testing 18858...51921 [N-1/N+1, Brillhart-Lehmer-Selfridge]
Running N-1 test using base 19
Running N-1 test using base 23
Running N+1 test using discriminant 47, base 1+sqrt(47)
Calling N-1 BLS with factored part 0.08% and helper 0.01% (0.24% proof)
18858...51921 is Fermat and Lucas PRP! (133.8058s+0.0221s)

To be completed...