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Number of isomorphism classes of simply embedded (i.e., loop-free and without parallel edges bounding a disk) quadrangulations of RP^2 of minimum degree 3 with n nodes and n-1 faces.
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%I #26 Jul 16 2017 20:59:50

%S 1,0,2,3,6,12,37,95,293,923,3086,10504,36954,131590,475793

%N Number of isomorphism classes of simply embedded (i.e., loop-free and without parallel edges bounding a disk) quadrangulations of RP^2 of minimum degree 3 with n nodes and n-1 faces.

%C Also the number of isomorphism classes of basic nets (polyhedra) on RP^2 with n-1 nodes and n faces.

%C Also the number of isomorphism classes of simple quadrangulations of the sphere of minimum degree 3 with 2n nodes and 2n-2 faces which admit an orientation reversing involution without fix nodes and fix edges.

%H S. Yu. Orevkov, <a href="http://arxiv.org/abs/1307.7377">Basic nets in the projective plane</a>

%Y Cf. A078666, A187014.

%K nonn,more

%O 4,3

%A _Stepan Orevkov_, Aug 30 2013