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 A121286 #12 Feb 12 2023 13:40:13 %S A121286 1,3,9,26,72,192,496,1248,3072,7424,17664,41472,96256,221184,503808, %T A121286 1130496,2555904,5701632 %N A121286 Number of catacondensed hexagonal systems with n hexagons. %C A121286 This is the erroneous version published by Tosic et al. The correct sequence is in A072863. - _R. J. Mathar_, May 21 2018 %H A121286 Tosic R., Masulovic D., Stojmenovic I., Brunvoll J., Cyvin B. N. and Cyvin S. J., <a href="http://dx.doi.org/10.1021/ci00024a002">Enumeration of polyhex hydrocarbons to h = 17</a>, J. Chem. Inf. Comput. Sci., 1995, 35, 181-187 Table 1 with an error at h=16. %K A121286 dead %O A121286 1,2 %A A121286 _Parthasarathy Nambi_, Sep 06 2006