%I M2493 #12 Mar 30 2012 16:45:08
%S 0,0,0,1,1,3,5,14,27,65,142,338,773,1832,4296,10231,24296,58128,
%T 139132,334350,804441,1940239,4685806,11335797,27455949,66585170,
%U 161646826
%N Number of symmetry sites in all planted 3-trees with n nodes.
%D Bailey, C. K.; Fundamental orbits. Proceedings of the second West Coast conference on combinatorics, graph theory and computing (Eugene, Ore., 1983). Congr. Numer. 41 (1984), 149-152.
%D Bailey, C. K.; Palmer, E. M.; Kennedy, J. W.; Points by degree and orbit size in chemical trees. II. Discrete Appl. Math. 5 (1983), no. 2, 157-164.
%D R. W. Robinson, personal communication.
%D N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence).
%H <a href="/index/Ro#rooted">Index entries for sequences related to rooted trees</a>
%H <a href="/index/Tra#trees">Index entries for sequences related to trees</a>
%K nonn
%O 1,6
%A _N. J. A. Sloane_.