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 A033854 #15 Feb 19 2021 03:34:38 %S A033854 3,4,8,15,20,28,40,102,132,140,252,360,510,780 %N A033854 Numbers k such that j(k)*ud(k)=phi(k), j(n) = A033831, ud(n) = number of unitary divisors of n (A034444). %C A033854 If it exists, a(15) > 10^9. - _Sean A. Irvine_, Jul 20 2020 %Y A033854 Cf. A000010 (phi), A033831, A034444. %K A033854 more,nonn %O A033854 1,1 %A A033854 _Naohiro Nomoto_