%I #3 Mar 30 2012 16:50:41
%S 0,1,0,1,1,3,7,16,44,134,433,1483,5196,18795,68845
%N Number of n-node triangulations of the projective plane N_1 in which every node has degree >= 5.
%D G. Ringel, Wie man die geschlossenen nichtorientierbaren Flaechen in moeglichst wenig Dreiecke zerlegen kann, Math. Ann. 130 (1955), 317-326.
%H Thom Sulanke, <a href="http://hep.physics.indiana.edu/~tsulanke/graphs/surftri/">Generating triangulations of surfaces (surftri)</a>, (also subpages).
%K nonn
%O 5,6
%A _N. J. A. Sloane_, May 13 2007