A286743 - OEIS

%I #4 May 14 2017 00:19:28

%S 0,0,1,5,24,136,1007,12270,274515,12004839,1018997154,165091170991,

%T 50502031364294,29054155657226889,31426485969804288254,

%U 64001015704527557845023,245935864153532932683596813,1787577725145611700547877883649,24637809253125004524383007490657239

%N Number of (not necessarily connected) simple cyclic graphs on n vertices.

%H Eric Weisstein's World of Mathematics, <a href="http://mathworld.wolfram.com/CyclicGraph.html">Cyclic Graph</a>

%F a(n) = A000088(n) - A005195(n).

%Y Cf. A000088 (number of simple graphs on n vertices).

%Y Cf. A005195 (number of forests with n unlabeled nodes).

%Y Cf. A241841 (number of simple connected graphs on n nodes that are not trees, i.e., number of connected cyclic graphs).

%K nonn

%O 1,4

%A _Eric W. Weisstein_, May 13 2017