Near-repdigit probable prime
http://homepage2.nifty.com/m_kamada/math/factorizations.htm
PFGW Version 3.4.8.64BIT.20110617.Win_Dev [GWNUM 26.6]
Primality testing (19*10^74253-1)/9 [N-1/N+1, Brillhart-Lehmer-Selfridge]
Running N-1 test using base 7
Running N+1 test using discriminant 13, base 1+sqrt(13)
(19*10^74253-1)/9 is Fermat and Lucas PRP! (1704.2424s+0.0024s)

To be completed...