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 A290571 #81 Nov 24 2017 23:14:17 %S A290571 1,1,2,4,7,22,60,208,695,2566,9451,36158,139574,548347,2174801, %T A290571 8719651,35244472,143581782,588858667,2430036786,10083626092, %U A290571 42055927173,176217259551,741517642476,3132564196880,13281805256068,56503895845238,241135999611542 %N A290571 Number of dissections of an n-gon into 3- and 5-gons counted up to rotations and reflections. %H A290571 Andrew Howroyd, <a href="/A290571/b290571.txt">Table of n, a(n) for n = 3..200</a> %H A290571 E. Krasko, A. Omelchenko, <a href="http://www.combinatorics.org/ojs/index.php/eljc/article/view/v22i1p17">Brown's Theorem and its Application for Enumeration of Dissections and Planar Trees</a>, The Electronic Journal of Combinatorics, 22 (2015), #P1.17. %e A290571 For a(5) = 2 the dissections of a pentagon are: a dissection into 3 triangles; a dissection into one pentagon. %o A290571 (PARI) \\ See A295419 for DissectionsModDihedral(). %o A290571 DissectionsModDihedral(apply(v->v==3||v==5, [1..25])) \\ _Andrew Howroyd_, Nov 22 2017 %Y A290571 Cf. A001004, A290646, A295260. %K A290571 nonn %O A290571 3,3 %A A290571 _Evgeniy Krasko_, Sep 03 2017 %E A290571 Terms a(16) and beyond from _Andrew Howroyd_, Nov 22 2017