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%I #19 Apr 20 2024 04:17:22
%S 0,0,0,0,0,0,1,3,27,146,492,1336,3156,7082,14938,29282,55012,100707,
%T 178063,306310,514381,846627,1370257
%N Number of five-prime Carmichael numbers less than 10^n.
%H Claude Goutier, <a href="http://www-labs.iro.umontreal.ca/~goutier/OEIS/A055553/">Text file readme.text summarizing enumeration of Carmichael numbers up to 10^22</a>.
%H Claude Goutier, <a href="/A055553/a055553.txt">Text file readme.text summarizing enumeration of Carmichael numbers up to 10^22</a>. [Local copy, with permission]
%H R. G. E. Pinch, <a href="http://s369624816.websitehome.co.uk/rgep/p82p.pdf">The Carmichael numbers up to 10^21</a>, Proceedings of Conference on Algorithmic Number Theory 2007.
%e For n=6, the smallest Carmichael number with 5 prime factors is 825265 = 5*7*17*19*73.
%Y For k-prime Carmichael numbers up to 10^n for k = 3,4,...,11, see A132195, A174612, A174613, A174614, A174615, A174616, A174617, A299710, A299711.
%Y Cf. A002997, A006931, A055553.
%K nonn,more
%O 0,8
%A _Michel Lagneau_, Mar 23 2010
%E a(22) from _Claude Goutier_ added by _Amiram Eldar_, Apr 19 2024