%I #3 Sep 09 2014 00:43:34
%S 1,2,31,1272,105720
%N Number of connected bicubical multigraphs on 2n labeled nodes of two colors.
%C Read's 1971 letter includes additional terms for both this sequence and A001500. But the terms a(6) and a(7) given for A001500 are wrong, so presumably those for this sequence are also wrong. See A246968 and A246969 for the sequences as given in Read's letter and (presumably) also in his dissertation.
%D R. C. Read, Some Enumeration Problems in Graph Theory. Ph.D. Dissertation, Department of Mathematics, Univ. London, 1958.
%H R. C. Read, <a href="/A002831/a002831.pdf">Letter to N. J. A. Sloane, Feb 04 1971</a>
%Y Cf. A001500, A246968, A246969.
%K nonn,more
%O 1,2
%A _N. J. A. Sloane_, Sep 09 2014