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%I #8 Jan 22 2018 08:58:24
%S 1,1,2,3,6,10,25,49,127,291,766,1843,5003,12487,34151,87983,242088,
%T 634848,1763749,4688677,13085621,35241441,98752586,268282856,
%U 755353825,2067175933,5837592853,16087674276,45550942142,126186554309,358344530763,997171512999
%N Number of unlabeled rooted trees with n nodes such that every branch of the root has the same number of nodes.
%H Alois P. Heinz, <a href="/A298537/b298537.txt">Table of n, a(n) for n = 1..1000</a>
%F a(n + 1) = Sum_{d|n} binomial(A000081(n/d) + d - 1, d).
%e The a(5) = 6 trees: ((((o)))), (((oo))), ((o(o))), ((ooo)), ((o)(o)), (oooo).
%t r[n_]:=r[n]=If[n===1,1,Sum[Product[Binomial[r[x]+Count[ptn,x]-1,Count[ptn,x]],{x,Union[ptn]}],{ptn,IntegerPartitions[n-1]}]];
%t Table[If[n===1,1,Sum[Binomial[r[(n-1)/d]+d-1,d],{d,Divisors[n-1]}]],{n,40}]
%Y Cf. A000081, A003238, A004111, A032305, A289078, A289079, A290689, A291443, A297791, A298422, A298533, A298535, A298538, A298539.
%K nonn
%O 1,3
%A _Gus Wiseman_, Jan 20 2018