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 A258013 #17 Feb 16 2025 08:33:25 %S A258013 1,127,2014,7918,31606,32122,32188,126394,127930,128476,486838,503254, %T A258013 503482,505306,505564,506332,511450,511462,511708,511804,513514, %U A258013 513772,513778,514540,514804,514936,2012890,2012902,2013916,2021098,2021212,2022124,2025196,2039254,2043610,2043622,2045674,2045788,2046700 %N A258013 Capped binary boundary codes for fusenes, only the maximal representatives of each equivalence class obtained by rotating. %C A258013 A258017(n) gives the count of terms with binary width 2n + 1. %C A258013 Differs from A258003 for the first time at n=875, which here contains a(875) = 131821024 the smallest polyhex (26 edges, six hexes) where two hexes (at the opposite ends of a coiled pattern) meet to touch each other. %C A258013 This pattern is isomorphic to benzenoid [6]Helicene (up to chirality, see the illustrations at Wikipedia-page). %C A258013 Note that here, in contrast to "Boundary Edges Code for Benzenoid Systems" (see links at A258012), if a fusene has no bilateral symmetry then both variants of the corresponding one-sided fusene (their codes) are included in this sequence, the other obtained from the other by turning it over. %H A258013 Antti Karttunen, <a href="/A258013/b258013.txt">Table of n, a(n) for n = 0..875</a> %H A258013 Eric Weisstein's World of Mathematics, <a href="https://mathworld.wolfram.com/Fusene.html">Fusene</a> %H A258013 Wikipedia, <a href="http://en.wikipedia.org/wiki/Helicene">Helicene</a> %Y A258013 Subsequences: A258003, A258015. %Y A258013 Intersection of A257250 and A258012. %Y A258013 Cf. A258014 (same codes without the most significant bit). %Y A258013 Cf. also A258017. %K A258013 nonn,base %O A258013 0,2 %A A258013 _Antti Karttunen_, May 31 2015