J. Sorenson and J. Webster, Strong pseudoprimes to twelve prime
bases, Math. Comp. 86(304):985-1003, 2017.
teach primes(6) to enumerate primes up to 2^64 - 1. Until Sorenson
and Webster's paper, we did not know how many strong speudoprime tests
were required when testing alleged primes between 3825123056546413051
and 2^64 - 1.
Reported by: Luiz Henrique de Figueiredo
Relnotes: primes(6) now enumerates primes beyond 3825123056546413050,
up to a new limit of 2^64 - 1.
MFC After: 1 week
