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 A287652 #5 Feb 16 2025 08:33:46 %S A287652 0,1,6,116,10888 %N A287652 Number of simple disconnected perfect matching graphs on 2n nodes. %H A287652 Eric Weisstein's World of Mathematics, <a href="https://mathworld.wolfram.com/DisconnectedGraph.html">Disconnected Graph</a> %H A287652 Eric Weisstein's World of Mathematics, <a href="https://mathworld.wolfram.com/PerfectMatching.html">Perfect Matching</a> %F A287652 a(n) = A218462(n) - A218463(n). %Y A287652 Cf. A218462 (simple not-necessarily connected perfect matching graphs). %Y A287652 Cf. A218463 (connected perfect matching graphs). %K A287652 nonn,more %O A287652 1,3 %A A287652 _Eric W. Weisstein_, May 29 2017