2,1

J. P. McSorley, Counting structures in the Moebius ladder, Discrete Math., 184 (1998), 137-164.

Sequence in context: A102993 A143416 A164698 this_sequence A046467 A132184 A143322

Adjacent sequences: A020877 A020878 A020879 this_sequence A020881 A020882 A020883

nonn,easy,more

N. J. A. Sloane (njas(AT)research.att.com).