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A160447 Number of isomorphism classes of n-fold coverings of a connected graph with Betti number 5. 2
1, 32, 1393, 336465, 207388305, 268749463729, 645244638648481, 2642912633259448386, 17340131659334061379490, 173401255467914281827442642, 2538767439061885080225425717858, 52643878634689290630033137748571475 (list; graph; refs; listen; history; text; internal format)
OFFSET

1,2

COMMENTS

Number of orbits of the conjugacy action of Sym(n) on Sym(n)^5 [Kwak and Lee, 2001]. - Álvar Ibeas, Mar 24 2015

REFERENCES

J. H. Kwak and J. Lee, Enumeration of graph coverings, surface branched coverings and related group theory, in Combinatorial and Computational Mathematics (Pohang, 2000), ed. S. Hong et al., World Scientific, Singapore 2001, pp. 97-161.

LINKS

Álvar Ibeas, Table of n, a(n) for n = 1..60

J. H. Kwak and J. Lee, Isomorphism classes of graph bundles. Can. J. Math., 42(4), 1990, pp. 747-761.

PROG

(Sage) sum([p.aut()**4 for p in Partitions(n)]) # Álvar Ibeas, Mar 24 2015

CROSSREFS

Sixth column of A160449.

Sequence in context: A241800 A231040 A254152 * A302263 A302963 A302806

Adjacent sequences:  A160444 A160445 A160446 * A160448 A160449 A160450

KEYWORD

nonn

AUTHOR

N. J. A. Sloane, Nov 12 2009

EXTENSIONS

Name clarified and more terms added by Álvar Ibeas, Mar 24 2015

STATUS

approved

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Last modified October 17 15:01 EDT 2019. Contains 328116 sequences. (Running on oeis4.)