%I A125679
%S A125679 9,44,655,42426,11590894,12561206794
%N A125679 Number of combinatorial 2-manifolds with n vertices.
%H A125679 Basudeb Datta, <a href="http://arXiv.org/abs/math/0701735">Minimal Triangulations
of Manifolds</a>, 25 Jan 2007, arXiv:math/0701735
%e A125679 a(7) = 9 because there are exactly nine 7-vertex combinatorial 2-manifolds,
five of which triangulate the 2-sphere S^2, three of which triangulate
RP^2 and one triangulates S^1 X S^1.
%e A125679 a(8) = 44 because there are exactly fortyfour 8-vertex combinatorial
2-manifolds, one of which consists of two copies of S(_4)^2, fourteen
of which triangulate the 2-sphere S^2, sixteen of which triangulate
RP^2, seven triangulate S^1 X S^1 and six triangulate the Klein bottle.
%Y A125679 Sequence in context: A099867 A104470 A084016 this_sequence A037207 A096688
A124983
%Y A125679 Adjacent sequences: A125676 A125677 A125678 this_sequence A125680 A125681
A125682
%K A125679 hard,nonn
%O A125679 7,1
%A A125679 Jonathan Vos Post (jvospost3(AT)gmail.com), Jan 30 2007
%E A125679 Replaced arXiv URL by non-cached version - R. J. Mathar (mathar(AT)strw.leidenuniv.nl),
Oct 30 2009
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