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A276109 The number of non-isomorphic drawings of the complete graph K_n such that any two edges intersect at most once (a.k.a. "good drawings" or "simple topological graphs"). 2
1, 2, 5, 121, 46999, 502090394 (list; graph; refs; listen; history; text; internal format)
OFFSET

3,2

REFERENCES

H.-D. O. F. Gronau and H. Harborth, Numbers of nonisomorphic drawings for small graphs, Congressus Numerantium, 71:105-114, 1990.

H. Harborth and I. Mengersen, Drawings of the complete graph with maximum number of crossings, Congressus Numerantium, 88:225-228, 1992.

LINKS

Table of n, a(n) for n=3..8.

B. M. Ábrego, O. Aichholzer, S. Fernández-Merchant, T. Hackl, J. Pammer, A. Pilz, P. Ramos, G. Salazar, and B. Vogtenhuber, All Good Drawings of Small Complete Graphs, In Proc. 31st European Workshop on Computational Geometry EuroCG '15, pages 57-60, Ljubljana, Slovenia, 2015.

J. Kynčl, Enumeration of simple complete topological graphs, European Journal of Combinatorics, 30(7):1676-1685, 2009.

CROSSREFS

Cf. A000241.

Coincides with A276110 for n <= 5.

Sequence in context: A015172 A132526 A294513 * A270481 A225944 A270588

Adjacent sequences:  A276106 A276107 A276108 * A276110 A276111 A276112

KEYWORD

nonn,more

AUTHOR

Manfred Scheucher, Aug 18 2016

STATUS

approved

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Last modified September 19 15:17 EDT 2021. Contains 347564 sequences. (Running on oeis4.)