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 A336785 #25 Sep 20 2020 19:01:51 %S A336785 1,2,3,4,8,7,10,15,13,18,18,29,22,31,29,35,36,42,53,52,55,68,82,66,87, %T A336785 80,87,116,124,104,124,100,132,142,160,166,161,190,173,182,237,244, %U A336785 289,312,331,265,259,269,265,330,386,495,565,542,449,381,436,465,486 %N A336785 Consider the rectangular regions in the Even Conant Lattice; let S(0) be the singleton with the square at the origin, and for any n >= 0, let S(n+1) be the set of rectangular regions adjacent to some region in S(n) that are not found in S(0) U ... U S(n); a(n) is the number of regions in S(n). %C A336785 See A328078 for more information. %C A336785 Two regions are considered adjacent if they share a common edge portion of size >= 1. %C A336785 This is the coordination series (with respect to the point at the origin) for the dual graph to the graph of the Even Conant Lattice. - _N. J. A. Sloane_, Sep 20 2020 %H A336785 Rémy Sigrist, <a href="/A336785/b336785.txt">Table of n, a(n) for n = 0..338</a> %H A336785 Rémy Sigrist, <a href="/A336785/a336785.png">Illustration of initial terms</a> %H A336785 Rémy Sigrist, <a href="/A336785/a336785.txt">C++ program for A336785</a> %H A336785 <a href="/index/Con#coordination_sequences">Index entries for coordination sequences</a> %e A336785 See Illustration in Links section. %o A336785 (C++) See Links section. %Y A336785 Cf. A328078, A337642. %K A336785 nonn %O A336785 0,2 %A A336785 _Rémy Sigrist_, Sep 20 2020