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 A193130 #18 Feb 16 2025 08:33:15 %S A193130 0,4,384,82944,32768000,20736000000,19271206305792,24759631762948096, %T A193130 42071440246337175552,91403961001574400000000, %U A193130 247248735803801600000000000,815050629127324260701847945216,3217014140995401936351315753959424 %N A193130 Numbers of spanning trees of the cocktail party graphs. %C A193130 Number of trees on 2n labeled vertices containing no edges from a prescribed perfect matching. - _Joel B. Lewis_, Jun 20 2013 %D A193130 Dragoš M. Cvetković, Michael Doob, Horst Sachs, Spectra of Graphs: Theory and Application, Academic Press, 1980. %H A193130 Takashi Horiyama, Masahiro Miyasaka, Riku Sasaki, <a href="https://www.cs.umanitoba.ca/~cccg2018/papers/session7B-p2.pdf">Isomorphism Elimination by Zero-Suppressed Binary Decision Diagrams</a>, 30th Canadian Conference on Computational Geometry, 2018. See Table 2. %H A193130 Eric Weisstein's World of Mathematics, <a href="https://mathworld.wolfram.com/CocktailPartyGraph.html">Cocktail Party Graph</a> %H A193130 Eric Weisstein's World of Mathematics, <a href="https://mathworld.wolfram.com/SpanningTree.html">Spanning Tree</a> %F A193130 a(n) = n^(n-2) * (n-1)^n * 4^(n-1). [See "Spectra of graphs", p. 217; also observed by _Joel B. Lewis_, Jun 20 2013] - _Andrey Zabolotskiy_, Mar 18 2021 %Y A193130 Cf. A091159 (up to isomorphism). %K A193130 nonn,easy %O A193130 1,2 %A A193130 _Eric W. Weisstein_, Jul 16 2011