A135717 - OEIS

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A135717

a(n) = number of prime divisors of Carmichael numbers A002997(n).

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: A379095 A335550 A243129 * A335465 A079083 A176171

Adjacent sequences: A135714 A135715 A135716 * A135718 A135719 A135720

KEYWORD

nonn

AUTHOR

Artur Jasinski, Nov 25 2007

STATUS

approved