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A135717 a(n) = number of prime divisors of Carmichael numbers A002997(n). 9
3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 4, 3, 3, 4, 4, 4, 4, 3, 4, 3, 4, 4, 3, 4, 3, 3, 3, 4, 3, 3, 4, 3, 3, 3, 4, 4, 4, 4, 4, 5, 4, 4, 4, 3, 4, 5, 4, 3, 3, 3, 4, 3, 4, 3, 3, 4, 4, 4, 4, 3, 4, 4, 4, 3, 4, 4, 3, 4, 3, 3, 4, 4, 4, 4, 4, 3, 3, 4, 3, 3, 4, 3, 4, 4, 3, 4, 3, 4, 3, 3, 3, 4, 3, 4, 4, 4, 4, 4, 4, 3, 4, 4, 4, 4, 5 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,1

COMMENTS

Number of prime divisors is always >= 3. For the least Carmichael number with n prime factors see A006931.

LINKS

Amiram Eldar, Table of n, a(n) for n = 1..10000

FORMULA

a(n) = A001221(A002997(n)). - M. F. Hasler, Apr 14 2015

CROSSREFS

Cf. A002997, A006931.

Sequence in context: A053444 A175797 A243129 * A079083 A176171 A032568

Adjacent sequences:  A135714 A135715 A135716 * A135718 A135719 A135720

KEYWORD

nonn

AUTHOR

Artur Jasinski, Nov 25 2007

STATUS

approved

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Last modified May 25 20:58 EDT 2020. Contains 334597 sequences. (Running on oeis4.)