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%I #15 Jun 12 2022 03:00:12
%S 0,0,1,1,2,3,6,11,23,46,98,207,451,983,2179,4850,10905,24631,56011,
%T 127912,293547,676157,1563372,3626149,8436379,19680277,46026618,
%U 107890609,253450711,596572387,1406818759,3323236238,7862958391
%N Number of n-node rooted unlabeled trees with outdegree <= 2 and exactly 1 edge at the root.
%H <a href="/index/Ro#rooted">Index entries for sequences related to rooted trees</a>
%p G036656 := G001190-x; A036656 := n->coeff(G036656,x,n);
%t terms = 33; A[_] = 0; Do[A[x_] = x + (1/2)*(A[x]^2 + A[x^2]) + O[x]^terms // Normal, terms];
%t CoefficientList[A[x] - x, x] (* _Jean-François Alcover_, Jan 24 2018 *)
%Y Except for initial terms, same as A001190.
%K nonn
%O 0,5
%A _N. J. A. Sloane_
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