Juan Navarro Muņoz wrote

> S is Fermat and Lucas PRP
> T is Fermat and Lucas PRP

To prove the claim in the title, one needs to prove primality of S and T.
This might be done using ECPP.

For an example of a 6-Carmichael number with 19140 digits, see

http://primes.utm.edu/primes/page.php?id=63867
http://primes.utm.edu/primes/page.php?id=63866
http://primes.utm.edu/primes/page.php?id=63865
http://primes.utm.edu/primes/page.php?id=63872
http://primes.utm.edu/primes/page.php?id=63871
http://primes.utm.edu/primes/page.php?id=63870

for the proven prime factors.

David Broadhurst



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