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 A055907 #21 Jun 21 2022 08:57:10 %S A055907 0,1,1,1,2,1,1,4,4,1,1,6,10,6,1,1,9,21,20,8,1,1,12,39,53,36,10,1,1,16, %T A055907 67,121,128,56,12,1,1,20,107,249,388,240,74,14,1,1,25,163,471,1050, %U A055907 854,331,100,16,1,1,30,238,836,2601,2654,1212,511,130,18,1,1,36,337 %N A055907 Triangle: number of directed site animals on hexagonal net (honeycomb) with n total sites and k sites supported in one particular way. %H A055907 A. J. Guttmann, <a href="https://doi.org/10.1016/S0012-365X(99)00262-9">Indicators of solvability for lattice models</a>, Discrete Math., 217 (2000), 167-189 (A_h of Section 6). %H A055907 A. J. Guttmann and A. R. Conway, <a href="https://blogs.unimelb.edu.au/tony-guttmann/files/2019/09/hexfinal.pdf">Hexagonal lattice directed site animals</a>, Statistical Physics on the Eve of the Twenty-First Century, ed. M. T. Batchelor, World Scientific, 1999 (F_h of Section 4). %e A055907 Table begins: %e A055907 0; %e A055907 1, 1; %e A055907 1, 2, 1; %e A055907 1, 4, 4, 1; %e A055907 1, 6, 10, 6, 1; %e A055907 ... %Y A055907 Row sums give A055919. %Y A055907 Columns 1-9 give: A002620(n+1), A055908, A055909, A055910, A055911, A055912, A055913, A055914, A055915. %Y A055907 Cf. A055898. %K A055907 nonn,tabl %O A055907 0,5 %A A055907 _Christian G. Bower_, Jun 14 2000 %E A055907 Name edited by _Andrey Zabolotskiy_, Jun 21 2022