OFFSET
1,1
COMMENTS
These numbers:
- are pseudoprimes to bases 2, 3 and 5;
- do not occur in A097130 (Carmichael numbers that are not == 1 mod 24).
The number (6*k + 1)*(24*k + 1)*(30*k + 1) is in the sequence if:
- k is congruent to 5 mod 10;
- its three factors are all prime.
LINKS
Amiram Eldar, Table of n, a(n) for n = 1..10000
Eric Weisstein's World of Mathematics, Carmichael Number.
PROG
(Magma) [a : k in [1..1785 by 2] | IsOne(a mod CarmichaelLambda(a)) where a is (6*k+1)*(24*k+1)*(30*k+1)]
CROSSREFS
KEYWORD
nonn
AUTHOR
Arkadiusz Wesolowski, Oct 28 2013
STATUS
approved