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A240973 The number of switching equivalent classes of cube root edge weighted graphs. 0
2, 4, 14, 120, 3222, 271287, 64154817, 41653775052, 74220906305025, 364602274426789164 (list; graph; refs; listen; history; text; internal format)
OFFSET

3,1

COMMENTS

a(n) is also the number of cube root two-graphs, up to isomorphism.

LINKS

Table of n, a(n) for n=3..12.

Y. Cheng and A. L. Wells,  Switching classes of directed graphs, Journal of Combinatorial Theory, Series B, Vol. 40-2 (1986), p. 169-186.

T. R. Hoffman and J. P. Solazzo, Complex two-graphs via equiangular tight frames, arXiv preprint, arXiv:1408.0334 [math.CO], 2014.

CROSSREFS

Sequence in context: A167008 A329234 A238638 * A102449 A193520 A102897

Adjacent sequences:  A240970 A240971 A240972 * A240974 A240975 A240976

KEYWORD

nonn,more

AUTHOR

Thomas R. Hoffman, Aug 05 2014

EXTENSIONS

a(8)-a(12) added by Andrew Howroyd, Aug 31 2018

STATUS

approved

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Last modified December 12 20:12 EST 2019. Contains 329961 sequences. (Running on oeis4.)