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Number of rooted trees with leaves of 2 colors where any 2 subtrees extending from the same node have a different number of nodes.
1

%I #10 Sep 20 2018 15:30:24

%S 2,2,2,6,10,26,66,174,442,1202,3298,9166,25674,72810,206826,595150,

%T 1712634,4978458,14494130,42502030,124660402,368221002,1087321354,

%U 3229266742,9591013738,28624735962,85404444970

%N Number of rooted trees with leaves of 2 colors where any 2 subtrees extending from the same node have a different number of nodes.

%H Andrew Howroyd, <a href="/A032306/b032306.txt">Table of n, a(n) for n = 1..500</a>

%H <a href="/index/Ro#rooted">Index entries for sequences related to rooted trees</a>

%F Shifts left under "EFK" (unordered, size, unlabeled) transform.

%o (PARI)

%o EFK(p,n)={prod(k=1, n, 1 + polcoef(p,k)*x^k + O(x*x^n))}

%o seq(n)={my(p=O(1)); for(i=1, n, p=1+EFK(x*p, i-1)); Vec(p)} \\ _Andrew Howroyd_, Sep 20 2018

%K nonn

%O 1,1

%A _Christian G. Bower_