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A055553 Number of Carmichael numbers (A002997) less than 10^n. 12
0, 0, 1, 7, 16, 43, 105, 255, 646, 1547, 3605, 8241, 19279, 44706, 105212, 246683, 585355, 1401644, 3381806, 8220777, 20138200 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,4

REFERENCES

Richard Pinch, Carmichael Numbers up to 10^20, ANTS 7.

LINKS

Table of n, a(n) for n=1..21.

Romeo Meštrović, Generalizations of Carmichael numbers I, arXiv:1305.1867v1 [math.NT], May 4, 2013.

R. G. E. Pinch, The Carmichael numbers up to 10^17

R. G. E. Pinch, The Carmichael numbers up to 10^{17}, April 2005.

R. G. E. Pinch, The Carmichael numbers up to 10^18

R. G. E. Pinch, Carmichael numbers up to 10^18, April 2006.

R. G. E. Pinch, The Carmichael numbers up to 10^21, May 2007; Proceedings of Conference on Algorithmic Number Theory 2007 - Charles R Greathouse IV, Feb 01 2009

R. G. E. Pinch, ANTS 7 Posters

Eric Weisstein's World of Mathematics, Carmichael Number

Eric Weisstein's World of Mathematics, Pseudoprime

CROSSREFS

Cf. A002997.

Sequence in context: A036834 A020941 A024625 * A066009 A037241 A154141

Adjacent sequences:  A055550 A055551 A055552 * A055554 A055555 A055556

KEYWORD

nonn

AUTHOR

Eric W. Weisstein

EXTENSIONS

Updates from Finch's articles sent by Charles R Greathouse IV, Dec 04 2005, Jul 16 2006, May 29 2007

a(21) from Richard Pinch's paper - Charles R Greathouse IV, Feb 01 2009

STATUS

approved

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Last modified December 6 08:53 EST 2016. Contains 278775 sequences.