PFGW Version 3.4.8.64BIT.20110617.Win_Dev [GWNUM 26.6]
Primality testing 21^43717+2 [N-1/N+1, Brillhart-Lehmer-Selfridge]
Running N-1 test using base 5
Running N-1 test using base 7
Running N+1 test using discriminant 17, base 1+sqrt(17)
Calling N+1 BLS with factored part 0.03% and helper 0.00% (0.08% proof)
21^43717+2 is Fermat and Lucas PRP! (352.7491s+0.0025s)

To be completed...