%I A052514
%S A052514 0,1,2,9,64,625,7056,89929,1284032,20351601,354648160,6736612201,
%T A052514 138472331328,3061103815081,72391319923664,1823032999274985,
%U A052514 48692068509655936,1374488205290880481,40877130077266074048
%N A052514 Number of labeled trees of height 4.
%H A052514 INRIA Algorithms Project, <a href="http://algo.inria.fr/bin/encyclopedia?Search=ECSnb&argsearch=60">
               Encyclopedia of Combinatorial Structures 60</a>
%F A052514 E.g.f.: x*exp(x*exp(x*exp(x*exp(x))))
%p A052514 spec := [S,{T2=Prod(Z,Set(T3)),S=Prod(Z,Set(T1)), T4=Z, T3=Prod(Z,Set(T4)), 
               T1=Prod(Z,Set(T2))},labeled]: seq(combstruct[count](spec,size=n), 
               n=0..20);
%Y A052514 Sequence in context: A036775 A141209 A128577 this_sequence A036776 A036777 
               A000169
%Y A052514 Adjacent sequences: A052511 A052512 A052513 this_sequence A052515 A052516 
               A052517
%K A052514 easy,nonn
%O A052514 0,3
%A A052514 encyclopedia(AT)pommard.inria.fr, Jan 25 2000