

A005967


Number of isomorphism classes of connected 3regular multigraphs of order 2n, loops allowed.
(Formerly M1512)


7



2, 5, 17, 71, 388, 2592, 21096, 204638, 2317172, 30024276, 437469859, 7067109598, 125184509147, 2410455693765, 50101933643655, 1117669367609605
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OFFSET

1,1


REFERENCES

A. T. Balaban, Enumeration of Cyclic Graphs, pp. 63105 of A. T. Balaban, ed., Chemical Applications of Graph Theory, Ac. Press, 1976; see p. 92.
Brendan McKay, software at http://users.cecs.anu.edu.au/~bdm/nauty/
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=1..16.


CROSSREFS

Cf. A129427, A000421, A085549, A129430, A129432, A129434, A129436
Sequence in context: A101900 A005966 A082282 * A104859 A108289 A007779
Adjacent sequences: A005964 A005965 A005966 * A005968 A005969 A005970


KEYWORD

nonn


AUTHOR

N. J. A. Sloane.


EXTENSIONS

Checked by Brendan McKay, Apr 15 2007
Using sequence A129427, terms a(12)  a(16) were computed in GAP by Ignat Soroko (ignat.soroko(AT)gmail.com), Apr 07 2010


STATUS

approved



