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This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

A202562 Carmichael numbers whose prime factors do not divide any smaller Carmichael number.

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%I A202562 #21 Feb 16 2025 08:33:16
%S A202562 561,84350561,851703301,2436691321,34138047673,60246018673,
%T A202562 63280622521,83946864769,110296864801,114919915021,155999871721,
%U A202562 225593397919,342267565249,534919693681,660950414671,733547013841,1079942171239,1301203515361,1333189866793
%N A202562 Carmichael numbers whose prime factors do not divide any smaller Carmichael number.
%C A202562 Note that all terms so far have only three prime factors.
%H A202562 Amiram Eldar, <a href="/A202562/b202562.txt">Table of n, a(n) for n = 1..10000</a> (calculated using data from Claude Goutier; terms 1..1377, terms below 10^18, from Donovan Johnson)
%H A202562 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 A202562 Eric Weisstein's World of Mathematics, <a href="https://mathworld.wolfram.com/CarmichaelNumber.html">Carmichael Number</a>.
%H A202562 <a href="/index/Ca#Carmichael">Index entries for sequences related to Carmichael numbers</a>.
%e A202562 a(2) = 84350561 because 84350561 = 107*743*1061 and the smaller Carmichael numbers do not have the factors 107, 743 or 1061.
%Y A202562 Cf. A002997, A087788.
%K A202562 nonn
%O A202562 1,1
%A A202562 _Arkadiusz Wesolowski_, Dec 21 2011