Hi All

190556231*997#+n*138880294*997#+1 (n=0-8) describes an AP9 of primes

424-425 digits

cheers
Ken

Primality testing 190556231*997#+0*138880294*997#+1 [N-1,
Brillhart-Lehmer-Selfridge]
Running N-1 test using base 2
Calling Brillhart-Lehmer-Selfridge with factored part 33.40%
190556231*997#+0*138880294*997#+1 is prime! (0.1372s+0.0014s)
Primality testing 190556231*997#+1*138880294*997#+1 [N-1,
Brillhart-Lehmer-Selfridge]
Running N-1 test using base 3
Calling Brillhart-Lehmer-Selfridge with factored part 33.55%
190556231*997#+1*138880294*997#+1 is prime! (0.1561s+0.0011s)
Primality testing 190556231*997#+2*138880294*997#+1 [N-1,
Brillhart-Lehmer-Selfridge]
Running N-1 test using base 7
Calling Brillhart-Lehmer-Selfridge with factored part 33.52%
190556231*997#+2*138880294*997#+1 is prime! (0.1743s+0.0012s)
Primality testing 190556231*997#+3*138880294*997#+1 [N-1,
Brillhart-Lehmer-Selfridge]
Running N-1 test using base 11
Calling Brillhart-Lehmer-Selfridge with factored part 33.74%
190556231*997#+3*138880294*997#+1 is prime! (0.1027s+0.0198s)
Primality testing 190556231*997#+4*138880294*997#+1 [N-1,
Brillhart-Lehmer-Selfridge]
Running N-1 test using base 19
Calling Brillhart-Lehmer-Selfridge with factored part 33.64%
190556231*997#+4*138880294*997#+1 is prime! (0.1545s+0.0013s)
Primality testing 190556231*997#+5*138880294*997#+1 [N-1,
Brillhart-Lehmer-Selfridge]
Running N-1 test using base 23
Calling Brillhart-Lehmer-Selfridge with factored part 33.71%
190556231*997#+5*138880294*997#+1 is prime! (0.1085s+0.0035s)
Primality testing 190556231*997#+6*138880294*997#+1 [N-1,
Brillhart-Lehmer-Selfridge]
Running N-1 test using base 31
Calling Brillhart-Lehmer-Selfridge with factored part 33.57%
190556231*997#+6*138880294*997#+1 is prime! (0.1355s+0.0034s)
Primality testing 190556231*997#+7*138880294*997#+1 [N-1,
Brillhart-Lehmer-Selfridge]
Running N-1 test using base 43
Running N-1 test using base 47
Calling Brillhart-Lehmer-Selfridge with factored part 33.85%
190556231*997#+7*138880294*997#+1 is prime! (0.1478s+0.0284s)
Primality testing 190556231*997#+8*138880294*997#+1 [N-1,
Brillhart-Lehmer-Selfridge]
Running N-1 test using base 59
Calling Brillhart-Lehmer-Selfridge with factored part 33.78%
190556231*997#+8*138880294*997#+1 is prime! (0.1455s+0.0237s)