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a(n) is the index of the smallest Carmichael number (A002997) with n prime divisors, or 0 if no such number exists.
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%I #25 Apr 20 2024 07:42:14

%S 1,11,40,403,1224,4886,19096,120137,485941,2974628,25293838

%N a(n) is the index of the smallest Carmichael number (A002997) with n prime divisors, or 0 if no such number exists.

%H Claude Goutier, <a href="http://www-labs.iro.umontreal.ca/~goutier/OEIS/A055553/">Compressed text file carm10e22.gz containing all the Carmichael numbers up to 10^22</a>.

%H Richard Pinch, <a href="http://s369624816.websitehome.co.uk/rgep/cartable.html">Tables relating to Carmichael numbers</a> (All the Carmichael numbers up to 10^18).

%F A002997(a(n)) = A006931(n). - _M. F. Hasler_, Apr 14 2015

%Y Cf. A002997, A135717, A006931.

%K nonn,more

%O 3,2

%A _Artur Jasinski_, Nov 25 2007

%E a(8)-a(11) from _Donovan Johnson_, Feb 23 2012

%E a(12) from _Amiram Eldar_, Jul 08 2019

%E Escape clause added by _Jianing Song_, Dec 12 2021

%E a(13) calculated using data from _Claude Goutier_ and added by _Amiram Eldar_, Apr 20 2024