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 A005503 M1248 #30 Feb 23 2021 10:06:24 %S A005503 1,2,4,11,28,91,291,1004,3471,12350,44114,159519,579835,2121845, %T A005503 7800702,28813730,106844383,397647256,1484755972,5560561040, %U A005503 20881939915,78617991116,296678132514,1121988213996,4251702739831,16141719280994,61389611762126,233856524866209 %N A005503 Number of unrooted triangulations of a disk with one internal node and n+3 nodes on the boundary. %C A005503 These are also called [1,n]-triangulations. %C A005503 Graphs can be enumerated and counted using the tool "plantri", in particular the command "./plantri -s -P[n] -c2m2 [n+1]". - _Manfred Scheucher_, Mar 08 2018 %D A005503 C. F. Earl and L. J. March, Architectural applications of graph theory, pp. 327-355 of R. J. Wilson and L. W. Beineke, editors, Applications of Graph Theory. Academic Press, NY, 1979. %D A005503 N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence). %H A005503 G. Brinkmann and B. McKay, <a href="http://users.cecs.anu.edu.au/~bdm/plantri/">Plantri (program for generation of certain types of planar graph)</a> %H A005503 C. F. Earl and L. J. March, <a href="/A005500/a005500_1.pdf">Architectural applications of graph theory</a>, pp. 327-355 of R. J. Wilson and L. W. Beineke, editors, Applications of Graph Theory. Academic Press, NY, 1979. (Annotated scanned copy) %H A005503 C. F. Earl & N. J. A. Sloane, <a href="/A005500/a005500.pdf">Correspondence, 1980-1981</a> %Y A005503 Row n=1 of the array in A169808. %K A005503 nonn %O A005503 0,2 %A A005503 _N. J. A. Sloane_ %E A005503 a(6) corrected and a(7)-a(14) from _Manfred Scheucher_, Mar 08 2018 %E A005503 Name clarified and terms a(15) and beyond from _Andrew Howroyd_, Feb 22 2021