1st PRP for 2^n-268349.

Sieved to P=200G.

Primality testing 2^43680-268349 [N-1/N+1, Brillhart-Lehmer-Selfridge]
Running N-1 test using base 107
Running N+1 test using discriminant 113, base 3+sqrt(113)
Calling N-1 BLS with factored part 0.15% and helper 0.05% (0.50% proof)
2^43680-268349 is Fermat and Lucas PRP! (105.7664s+0.0051s)

To be completed...