%I #12 Aug 06 2020 08:22:30
%S 20,32,52,120,240,640,1576,3696,9736,28712,85784
%N Number of graceful labelings of the n-pan graph.
%H Eric Weisstein's World of Mathematics, <a href="http://mathworld.wolfram.com/GracefulLabeling.html">Graceful Labeling</a>
%H Eric Weisstein's World of Mathematics, <a href="http://mathworld.wolfram.com/PanGraph.html">Pan Graph</a>
%H Wikipedia, <a href="https://en.wikipedia.org/wiki/Graceful_labeling">Graceful labeling</a>
%K nonn,more
%O 3,1
%A _Eric W. Weisstein_, Apr 03 2020
%E a(12)-a(13) from _Pontus von Brömssen_, Aug 06 2020