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 A283872 #28 Jul 24 2021 01:11:31 %S A283872 432046225,631071001,4579461601,8494657921,53282340865,80601412609 %N A283872 Numbers k such that gcd(phi(k), k-1) > lambda(k)^2. %C A283872 2320690177 is the only 2 < k < 10^11 such that gcd(phi(k),k-1) = lambda(k)^2. - _Giovanni Resta_, Mar 24 2017 %Y A283872 Cf. A000010, A002322, A049559, A264012, A283656. %K A283872 nonn,more %O A283872 1,1 %A A283872 _Thomas Ordowski_ and _Altug Alkan_, Mar 24 2017 %E A283872 a(3)-a(6) from _Giovanni Resta_, Mar 24 2017