%I A000184 M2128 N0843
%S A000184 2,22,164,1030,5868,31388,160648,795846,3845020,18211380,84876152,390331292,
%T A000184 1775032504
%N A000184 Number of rooted planar maps with n edges.
%D A000184 N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, 
               Academic Press, 1995 (includes this sequence).
%D A000184 N. J. A. Sloane, A Handbook of Integer Sequences, Academic Press, 1973 
               (includes this sequence).
%D A000184 Tutte, W. T.; On the enumeration of planar maps. Bull. Amer. Math. Soc. 
               74 1968 64-74.
%D A000184 T. R. S. Walsh, Combinatorial Enumeration of Non-Planar Maps. Ph.D. Dissertation, 
               Univ. of Toronto, 1971.
%D A000184 T. R. S. Walsh and A. B. Lehman, Counting rooted maps by genus, J. Comb. 
               Thy B13 (1972), 122-141 and 192-218.
%H A000184 Richard P. Stanley, <a href="http://www-math.mit.edu/~rstan/ec/catadd.pdf">
               CATALAN ADDENDUM</a>, version of Jul 19, 2008, p. 24. [From Jonathan 
               Vos Post (jvospost3(AT)gmail.com), Aug 16 2008]
%F A000184 Appears to be 2 * A029887(n). - R. Stephan, Aug 17 2004
%F A000184 a(n) = (2 * (2*n)! * 3^n)/(n! * (n+1)!) = ((2*(3^n))/(n+2))*C(n) where 
               C(n) is the n-th Catalan number, A000108(n). [From Jonathan Vos Post 
               (jvospost3(AT)gmail.com), Aug 16 2008]
%Y A000184 Sequence in context: A067057 A123960 A091169 this_sequence A007613 A043037 
               A058441
%Y A000184 Adjacent sequences: A000181 A000182 A000183 this_sequence A000185 A000186 
               A000187
%K A000184 nonn
%O A000184 2,1
%A A000184 N. J. A. Sloane (njas(AT)research.att.com).