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 A319322 #20 Dec 15 2021 00:20:04 %S A319322 1,3,11,44,184,784,3370,14544,62862,271804,1175133,5079516,21951384, %T A319322 94847528,409767878,1770177486 %N A319322 Number of row convex polyhexes with n cells. %C A319322 A polyhex is considered to be row convex if cells take contiguous positions in each row. (Multiple cells in a row are not connected.) %H A319322 Adam Gruber, <a href="https://devweb3000.cis.strath.ac.uk/~xpb16190/LatticeAnimals/LatticeAnimals.jar">Java program to count lattice animals</a>. %e A319322 The only pentahexes that are not row convex are the shallow V shape and its 180-degree rotation. So a(5) = A001207(5) - 2 = 184. %Y A319322 Cf. A001207 (fixed polyhexes), A059716 (column convex polyhexes). %K A319322 nonn,more %O A319322 1,2 %A A319322 _David Bevan_, Sep 18 2018