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 A290653 #24 Jan 08 2025 11:05:01 %S A290653 2,2,6,23,64,181 %N A290653 Number of perfect dissections of equilateral triangles into n equilateral triangles with integer sides. %C A290653 A perfect dissection has no two triangles of the same side. Triangles of different orientation are counted separately. The computation by A. Drapal and C. Hamalainen proves Tutte's conjecture that the smallest perfect dissection has size 15. %H A290653 Ales Drapal and Carlo Hamalainen, <a href="https://arxiv.org/abs/0910.5199">An enumeration of equilateral triangle dissections</a>, arXiv:0910.5199 [math.CO], 2009-2010. %H A290653 W. T. Tutte, <a href="https://doi.org/10.1017/S030500410002449X">The dissection of equilateral triangles into equilateral triangles</a>, Mathematical Proceedings of the Cambridge Philosophical Society, 44(4), 463-482. doi:10.1017/S030500410002449X %H A290653 Stuart Anderson, <a href="https://web.archive.org/web/20170806090944/http://www.squaring.net/tri/tritri/tet.html">An Introduction to Triangled Equilateral Triangles</a>. %H A290653 Stuart Anderson, <a href="https://web.archive.org/web/20170806090944/http://www.squaring.net/tri/petts/o15/o15pett.pdf">Illustration of dissections for n=15</a>. %H A290653 Stuart Anderson, <a href="https://web.archive.org/web/20170806090944/http://www.squaring.net/tri/petts/o16/o16pett.pdf">Illustration of dissections for n=16</a>. %H A290653 Stuart Anderson, <a href="https://web.archive.org/web/20170806090944/http://www.squaring.net/tri/petts/o17/o17pett.pdf">Illustration of dissections for n=17</a>. %H A290653 Stuart Anderson, <a href="https://web.archive.org/web/20170806090944/http://www.squaring.net/tri/petts/o18/o18pett.pdf">Illustration of dissections for n=18</a>. %H A290653 Stuart Anderson, <a href="https://web.archive.org/web/20170806090944/http://www.squaring.net/tri/petts/o19/o19pett.pdf">Illustration of dissections for n=19</a>. %H A290653 Stuart Anderson, <a href="https://web.archive.org/web/20170806090944/http://www.squaring.net/tri/petts/o20/o20pett.pdf">Illustration of dissections for n=20</a>. %Y A290653 Cf. A167123, A290697. %K A290653 nonn,more,hard %O A290653 15,1 %A A290653 _Hugo Pfoertner_, Aug 08 2017