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%I #8 Nov 02 2015 11:00:35
%S 1,0,420,36960,3651480,453448800,67528553400,11697130922400,
%T 2306595939347700,509359060543132800,124356566550728011500,
%U 33226132945543622884800,9635384706205021006042800
%N Number of labeled non-planar projective-planar 2-connected K_{3,3}-free homeomorphically irreducible graphs with n vertices.
%H A. Gagarin et al., <a href="/A135340/b135340.txt">Table of n, a(n) for n = 5..20</a>
%H A. Gagarin, G. Labelle and P. Leroux, <a href="http://arxiv.org/abs/math/0406140">Counting labeled projective-planar graphs without a K_{3,3}-subdivision</a>, arXiv:math/0406140 [math.CO], 2004-2006.
%Y Cf. A104592, A104593.
%K nonn
%O 5,3
%A _N. J. A. Sloane_, Dec 07 2007