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A174617 Number of nine-prime Carmichael numbers less than 10^n. 5
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 1, 27, 170, 1436, 8835, 44993, 196391, 762963, 2714473 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,15

LINKS

Table of n, a(n) for n=0..21.

R. G. E. Pinch, "The Carmichael numbers up to 10^21", Proceedings of Conference on Algorithmic Number Theory 2007

EXAMPLE

n=13, with 9 prime factors, the smallest Carmichael number is : 9746347772161 = 7*11*13*17*19*31*37*41*641.

CROSSREFS

Cf. A002997, A132195, A006931, A055553, A174612 - A174616.

Sequence in context: A042418 A042420 A213285 * A055339 A083560 A125337

Adjacent sequences:  A174614 A174615 A174616 * A174618 A174619 A174620

KEYWORD

nonn

AUTHOR

Michel Lagneau, Mar 23 2010

STATUS

approved

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Last modified September 2 23:10 EDT 2014. Contains 246369 sequences.