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A055553
Number of Carmichael numbers (A002997) less than 10^n.
61
0, 0, 1, 7, 16, 43, 105, 255, 646, 1547, 3605, 8241, 19279, 44706, 105212, 246683, 585355, 1401644, 3381806, 8220777, 20138200, 49679870
OFFSET
1,4
REFERENCES
Richard Pinch, Carmichael Numbers up to 10^20, ANTS 7.
Richard G. E. Pinch, The Carmichael numbers up to 10^21, Proceedings of Conference on Algorithmic Number Theory 2007.
LINKS
Claude Goutier, Compressed text file carm10e22.7z containing all the Carmichael numbers up to 10^22. [Local copy, with permission. This is a very large file.]
Romeo Meštrović, Generalizations of Carmichael numbers I, arXiv:1305.1867v1 [math.NT], May 4, 2013.
Richard G. E. Pinch, The Carmichael numbers up to 10^17, arXiv:math/0504119 [math.NT], 2005.
Richard G. E. Pinch, The Carmichael numbers up to 10^18, arXiv:math/0604376 [math.NT], 2006.
Richard G. E. Pinch, Mathematics research page.
Andrew Shallue and Jonathan Webster, Advances in Tabulating Carmichael Numbers, Research in Number Theory, Vol. 11, No. 8 (2025), pp. 1-8; arXiv preprint, arXiv:2401.14495 [math.NT], 2024.
Eric Weisstein's World of Mathematics, Carmichael Number.
Eric Weisstein's World of Mathematics, Pseudoprime.
CROSSREFS
Cf. A002997.
Sequence in context: A020941 A318750 A024625 * A066009 A304013 A037241
KEYWORD
nonn,more,changed
EXTENSIONS
Updates from Pinch's articles sent by Charles R Greathouse IV, Dec 04 2005, Jul 16 2006, May 29 2007
a(21) from Pinch's paper by Charles R Greathouse IV, Feb 01 2009
a(22) from Shallue and Webster (2024) added by Amiram Eldar, Feb 23 2024
a(22) = 49679870 reported by Claude Goutier on Dec 28 2022 (see links). - N. J. A. Sloane, Apr 18 2024
STATUS
approved