%I #6 Jan 22 2015 14:36:07
%S 1,1,6,42,313,2407,18848,149271,1191092,9553551,76910632
%N Hilbert series of combinatorial Hopf algebra H(Heap_2).
%H J.-P. Bultel, S. Giraudo, <a href="http://arxiv.org/abs/1406.6903">Combinatorial Hopf algebras from PROs</a>, arXiv preprint arXiv:1406.6903, 2014
%K nonn,more
%O 0,3
%A _N. J. A. Sloane_, Sep 21 2014