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%I #17 Dec 19 2015 14:15:13
%S 1,1,0,0,0,0,0,0,0,0,0,1,2,6,11,25,49,105,211,444,903,1880,3865,8042,
%T 16658,34764,72484,151856,318418,669934,1411637,2982407,6311760,
%U 13387127,28442458,60543586,129084965,275683061,589660911,1263128375
%N Number of asymmetric trees with a forbidden limb of length 3.
%C A tree with a forbidden limb of length k is a tree where the path from any leaf inward hits a branching node or another leaf within k steps.
%H Vaclav Kotesovec, <a href="/A052326/b052326.txt">Table of n, a(n) for n = 0..1000</a>
%H <a href="/index/Lu#Lyndon">Index entries for sequences related to Lyndon words</a>
%F G.f.: 1 + B(x) + x^4 + x^5 + x^6 - (B(x^2) + B(x)^2)/2 where B(x) is g.f. of A052325.
%F a(n) ~ c * d^n / n^(5/2), where d = 2.2767145838879762709809174486..., c = 0.15900430026983804503695298... . - _Vaclav Kotesovec_, Aug 25 2014
%Y Cf. A002955, A002988-A002992, A052318-A052329.
%K nonn
%O 0,13
%A _Christian G. Bower_, Dec 15 1999
%E More terms, formula and comments from _Christian G. Bower_, Dec 15 1999
%E Typo in cross-reference corrected by _Vaclav Kotesovec_, Aug 25 2014