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%I M2075
%S 2,15,60,175,420,882,1680,2970,4950,7865,12012,17745,25480,35700,
%T 48960,65892,87210,113715,146300,185955,233772,290950,358800,438750,
%U 532350,641277,767340,912485,1078800,1268520
%N Number of rooted planar maps.
%D N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence).
%D Walsh, T. R. S.; Lehman, A. B.; Counting rooted maps by genus. III: Nonseparable maps. J. Combinatorial Theory Ser. B 18 (1975), 222-259.
%F (n+1)*binomial(n+3, 4).
%F C(n+2, 2)*C(n+4, 3)/2; g.f.: x*(2+3*x)/(1-x)^6. - Zerinvary Lajos (zerinvarylajos(AT)yahoo.com), Dec 14 2005
%t f[n_]:=(n+(n+1)+(n+2))*n*(n+1)*(n+2)*(n+3)/72; lst={};Do[AppendTo[lst,f[n]],{n,0,5!}];lst [From _Vladimir Joseph Stephan Orlovsky_, Oct 08 2009]
%Y A027789/2.
%K nonn,easy
%O 1,1
%A _N. J. A. Sloane_.
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