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Also number of (n-1)-node labeled mating graphs without isolated nodes, cf. A006024. - Vladeta Jovovic, Mar 23 2004
Table of n, a(n) for n=1..15.
P. J. Cameron, Counting two-graphs related to trees, Elec. J. Combin., Vol. 2, #R4.
Sequence in context: A125485 A054337 A009685 * A080315 A022752 A000771
Adjacent sequences: A007830 A007831 A007832 * A007834 A007835 A007836
Peter J. Cameron