0,4
Assumed to be weakly connected.
F. Harary and E. M. Palmer, Graphical Enumeration, Academic Press, NY, 1973, p. 219 (but there is an error).
R. C. Read (rcread(AT)math.uwaterloo.ca), email to N. J. A. Sloane (njas(AT)research.att.com), 28 August, 2000.
Eric Weisstein's World of Mathematics, Eulerian Graph
Cf. A058338.
Sequence in context: A174463 A124191 A065087 * A025503 A078124 A115245
Adjacent sequences: A058334 A058335 A058336 * A058338 A058339 A058340
nonn,nice,more
N. J. A. Sloane (njas(AT)research.att.com).
