33837...42891 (56-digits)
This number is a prime.
338374 6409486665 5412810571 6448226708 1046924847 8083542891
This prime starts the largest known Cunningham chain of
length 12 as of 2008: (8428860*127# + 212148902055090) *
2^n + 1, for n = 0 to 11. It also contains the largest
known chain of length 11 which was actually the goal. There
just happened to be a 12th prime. The chains are of the
second kind. [Andersen]
Printed from the PrimePages <t5k.org> © G. L. Honaker and Chris K. Caldwell