

A006714


Number of trivalent bipartite labeled graphs with 2n labeled nodes.
(Formerly M4757)


1




OFFSET

3,1


COMMENTS

R. C. Read incorrectly has a(7) = 118257539400 and a(8) = 154678050727200 which he calculated by hand.  Sean A. Irvine, Jun 27 2017


REFERENCES

R. C. Read, Some Enumeration Problems in Graph Theory. Ph.D. Dissertation, Department of Mathematics, Univ. London, 1958.
N. J. A. Sloane and Simon Plouffe, The Encyclopedia of Integer Sequences, Academic Press, 1995 (includes this sequence).


LINKS

Table of n, a(n) for n=3..12.
R. C. Read, Letter to N. J. A. Sloane, Feb 04 1971 (gives initial terms of this sequence)


CROSSREFS

Cf. A246599.
Sequence in context: A013436 A013437 A246599 * A203533 A015033 A126677
Adjacent sequences: A006711 A006712 A006713 * A006715 A006716 A006717


KEYWORD

nonn,more


AUTHOR

N. J. A. Sloane.


EXTENSIONS

a(7)a(8) corrected and a(9)a(12) computed with nauty by Sean A. Irvine, Jun 27 2017


STATUS

approved



