OFFSET
1,1
COMMENTS
Numbers of the form: (6*m + 1) * (12*m + 1) * Product_{i=1..k-2} (9 * 2^i * m + 1), where k >= 4, with the condition that each of the factors is prime and that m is divisible by 2^(k-4).
LINKS
Daniel Suteu, Table of n, a(n) for n = 1..9944
Jack Chernick, On Fermat's simple theorem, Bull. Amer. Math. Soc. 45:4 (1939), pp. 269-274.
Daniel Suteu, Perl program
Eric Weisstein's World of Mathematics, Carmichael Number
CROSSREFS
KEYWORD
nonn
AUTHOR
Daniel Suteu, Jul 22 2018
STATUS
approved