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 A023995 #10 Jun 18 2019 03:31:55
%S A023995 1,2,4,6,12,16,32,44,64,86,172,204,408,544,660,860,1720,2080,4160,
%T A023995 4800,5792,7784,15568,17440,23648,31616,40976,46584,93168,102768,
%U A023995 205536,261600,316160,426304,479616,524112,1048224,1407856,1699568,1848384,3696768,4049376,8098752,9292544
%N A023995 Number of sets S = {a_1, a_2, ..., a_k}, with 1 < a_i < a_j <= n such that no a_j divides the product of all the others.
%H A023995 Sean A. Irvine, <a href="https://github.com/archmageirvine/joeis/blob/master/src/irvine/oeis/a023/A023995.java">Java program</a> (github)
%e A023995 f(4)=6: {}, {2}, {3}, {4}, {2,3}, {3,4}.
%Y A023995 Cf. A038199.
%K A023995 nonn
%O A023995 1,2
%A A023995 Lionel Levine (levine(AT)ultranet.com)
%E A023995 More terms from _Sean A. Irvine_, Jun 17 2019