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A214428
Carmichael numbers n such that A002322(n) = 2^k * p, where k is an integer and p is a prime.
1
561, 1105, 2465, 278545, 3224065, 11119105, 2479305985, 123155771490305
OFFSET
1,1
COMMENTS
Wright (2012) proves that given the 5 known Fermat primes (A019434), these are the only numbers possible.
LINKS
Eric Weisstein's World of Mathematics, Carmichael Function.
Thomas Wright, The impossibility of certain types of Carmichael numbers, INTEGERS 12 (2012), A31.
CROSSREFS
Cf. A002997 (Carmichael numbers), A002322, A019434, A293291.
Sequence in context: A083733 A339869 A375875 * A262043 A264012 A175737
KEYWORD
nonn,hard
AUTHOR
T. D. Noe, Jul 19 2012
STATUS
approved