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%I #18 Nov 03 2017 22:21:29
%S 1,5,95,10297,11546911
%N Number of simple connected perfect matching graphs on 2n nodes.
%C Perfect matchings exist only for graphs with an even number of nodes.
%H Eric Weisstein's World of Mathematics, <a href="http://mathworld.wolfram.com/ConnectedGraph.html">Connected Graph</a>
%H Eric Weisstein's World of Mathematics, <a href="http://mathworld.wolfram.com/PerfectMatching.html">Perfect Matching</a>
%F a(n) = A218462(n) - A287652(n). - _Eric W. Weisstein_, May 29 2017
%F Inverse Euler transform of A218462. - _Andrew Howroyd_, Nov 03 2017
%Y Cf. A218462 (not-necessarily-connected simple perfect matching graphs).
%Y Cf. A287652 (disconnected simple perfect matching graphs).
%K nonn,more
%O 1,2
%A _Eric W. Weisstein_, Mar 26 2013