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%I #4 May 10 2013 12:44:50
%S 1,1,3,10,39,164,746,3474,16658,81166,401169,2004517,10110757,
%T 51402250,263133142,1355126922,7016115632,36498130908,190673015083,
%U 999932115039,5262094054524,27779114013628,147072756065567,780722981065006
%N Number of 2-trees rooted at a triangle.
%D F. Harary and E. M. Palmer, Graphical Enumeration, Academic Press, NY, 1973, p. 76, Eq. (3.5.13).
%Y Cf. A005750, A058870, A058866, A054581.
%K nonn
%O 1,3
%A _Vladeta Jovovic_, Aug 22 2001