A104592 - OEIS

A104592

Number of labeled non-planar projective-planar 2-connected graphs without a K_{3,3}-subdivision and with n vertices.

%I #11 Nov 02 2015 10:33:14

%S 1,120,10920,988960,99706320,11897978400,1729153068720,

%T 306003079514880,64657337524631280,15890834362452489440,

%U 4435396700216405763840,1379778057502074926142720,471689356958791639787042560

%N Number of labeled non-planar projective-planar 2-connected graphs without a K_{3,3}-subdivision and with n vertices.

%C By empirical evidence, the terms possess a curious prime factor behavior. E.g. 2^7*3^2*5*11*17*19 divides a(19)=70291642269058321415718042668160.

%H A. Gagarin et al., <a href="/A104592/b104592.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. A104593, A135340.

%K nonn

%O 5,2

%A _Valery A. Liskovets_, Mar 22 2005