2,1
J. P. McSorley, Counting structures in the Moebius ladder, Discrete Math., 184 (1998), 137-164.
Sequence in context: A102993 A143416 A164698 * A046467 A132184 A143322
Adjacent sequences: A020877 A020878 A020879 * A020881 A020882 A020883
nonn,easy,more
N. J. A. Sloane (njas(AT)research.att.com).