%I A055553
%S A055553 0,0,1,7,16,43,105,255,646,1547,3605,8241,19279,44706,105212,246683,
%T A055553 585355,1401644,3381806,8220777,20138200
%N A055553 Number of Carmichael numbers (A002997) less than 10^n.
%D A055553 Richard Pinch, Carmichael Numbers up to 10^20, ANTS 7.
%H A055553 R. G. E. Pinch, <a href="http://arXiv.org/abs/math.NT/0504119">The Carmichael 
               numbers up to 10^17</a>
%H A055553 R. G. E. Pinch, <a href="http://www.chalcedon.demon.co.uk/rgep/p73.ps">
               The Carmichael numbers up to 10^{17}</a>, April 2005.
%H A055553 R. G. E. Pinch, <a href="http://arXiv.org/abs/math/0604376">The Carmichael 
               numbers up to 10^18</a>
%H A055553 R. G. E. Pinch, <a href="http://www.chalcedon.demon.co.uk/rgep/publish.html#76">
               Carmichael numbers up to 10^18</a>, April 2006.
%H A055553 R. G. E. Pinch, "The Carmichael numbers up to 10^21", <a href="http:/
               /www.tucs.fi/publications/insight.php?id=pErJuKaLe07a&table=proceeding">
               Proceedings of Conference on Algorithmic Number Theory 2007</a> [From 
               Charles R Greathouse IV Feb 01 2009]
%H A055553 R. G. E. Pinch, <a href="http://www.math.tu-berlin.de/~kant/ants/poster.html">
               ANTS 7 Posters</a>
%H A055553 Eric Weisstein's World of Mathematics, <a href="http://mathworld.wolfram.com/
               CarmichaelNumber.html">Link to a section of The World of Mathematics.</
               a>
%H A055553 Eric Weisstein's World of Mathematics, <a href="http://mathworld.wolfram.com/
               Pseudoprime.html">Link to a section of The World of Mathematics.</
               a>
%Y A055553 Cf. A002997.
%Y A055553 Sequence in context: A036834 A020941 A024625 this_sequence A066009 A037241 
               A154141
%Y A055553 Adjacent sequences: A055550 A055551 A055552 this_sequence A055554 A055555 
               A055556
%K A055553 nonn
%O A055553 1,4
%A A055553 Eric Weisstein (eric(AT)weisstein.com)
%E A055553 Updates from Finch's articles sent by Charles R. Greathouse IV, Dec 04 
               2005, Jul 16 2006, May 29 2007
%E A055553 a(21) from Richard Pinch's paper - Charles R Greathouse IV Feb 01 2009