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%I #19 Mar 01 2019 17:14:11
%S 1,2,5,8,10,14,15,16,17,18,22,23,25,27,28,30,33,35,38,40,42,49,50,56,
%T 61,64,65,67,68,71,73,74,75,76,77,78,82,84,87,93,98,99,104,108,113,
%U 114,115,117,118,119,120,121,122,123,124,127,128,135,137,138,139
%N Values of k such that the number of rooted trees with k nodes (A000081(k)) is odd.
%C Complement of A258592.
%t Module[{t}, t[1] = 1; t[k_] := t[k] = Sum[DivisorSum[k-m, t[#] # &] t[m]/(k-1), {m, k-1}]; Select[Range[140], OddQ@t[#] &]] (* after _Alois P. Heinz_ *)
%Y Cf. A000081, A211192, A258592.
%K nonn
%O 1,2
%A _Vladimir Reshetnikov_, Nov 03 2015
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