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.
%I A329948 #13 Apr 21 2024 10:00:00 %S A329948 9857524690572481,33439671284716801,96653613831890401, %T A329948 270136961300544031,528096456788419441,650643395658753601, %U A329948 710238404427321601,1822922951416158241,4011563714063821201,4525693104167627041,4631812281009523441,7049793086137296001,8605736094003523201,10449416165574628801,11175581620177915681,12746447178170148001,12769123623410580481,17705945296667070001 %N A329948 Carmichael numbers m that have at least 3 prime factors p such that p+1 | m+1. %C A329948 It is not known whether any Carmichael number (A002997) is also Lucas-Carmichael number (A006972). If such a number exists, then it would be a term of this sequence. %H A329948 Amiram Eldar, <a href="/A329948/b329948.txt">Table of n, a(n) for n = 1..179</a> (terms below 10^22, calculated using data from Claude Goutier) %H A329948 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 A329948 Wikipedia, <a href="https://en.wikipedia.org/wiki/Carmichael_number">Carmichael number</a>. %H A329948 Wikipedia, <a href="https://en.wikipedia.org/wiki/Lucas%E2%80%93Carmichael_number">Lucas-Carmichael number</a>. %e A329948 m = 9857524690572481 is a term because it is a Carmichael number and it has at least 3 prime factors p, {13, 61, 433}, such that p+1 | m+1. %o A329948 (Perl) use bigint; use ntheory ':all'; sub isok { my $m = $_[0]; is_carmichael($m) && (grep { ($m+1) % ($_+1) == 0 } factor($m)) >= 3 }; %Y A329948 Cf. A002997, A006972. %K A329948 nonn %O A329948 1,1 %A A329948 _Daniel Suteu_, Nov 25 2019