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 A027667 #8 Nov 19 2019 05:56:54 %S A027667 2,5,63,70633,25090373284177 %N A027667 Number of independent subsets of nodes of 3^n cube (P_3 X ... X P_3). %H A027667 Sean A. Irvine, <a href="https://github.com/archmageirvine/joeis/blob/master/src/irvine/oeis/a027/A027667.java">Java program</a> (github) %e A027667 For n=0, the two sets are the empty set and a set containing a single isolated vertex. - _Sean A. Irvine_, Nov 16 2019 %Y A027667 Cf. A027624 (P_2), A027668 (P_4). %K A027667 nonn,nice,hard,more %O A027667 0,1 %A A027667 _R. H. Hardin_ %E A027667 a(0) corrected by _Sean A. Irvine_, Nov 16 2019