%I M1884 #9 Mar 30 2012 16:45:08
%S 1,2,8,50,872,55056,14330784,14168055824,51063045165248,
%T 667216816957658368,31770676467810344050944,
%U 5550693121829253260986015232,3581419675678994222257101230830592,8583524017313906693161883558288460677120
%N Number of unlabeled strength 3 Eulerian graphs with n nodes.
%D R. W. Robinson, personal communication.
%D R. W. Robinson, Numerical implementation of graph counting algorithms, AGRC Grant, Math. Dept., Univ. Newcastle, Australia, 1979.
%D N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence).
%H R. W. Robinson, <a href="/A007128/b007128.txt">Table of n, a(n) for n = 1..22</a>
%K nonn
%O 1,2
%A _N. J. A. Sloane_.