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A281346 Related to enumeration of sets of non-intersecting circles in the plane. 0
1, 1, 4, 11, 41, 141, 537, 2041, 8042, 32028, 129780, 531331, 2198502, 9171233, 38545677, 163031436, 693470737, 2964491394, 12729640115, 54881425222, 237471970199, 1030935383055, 4489081879021, 19601108680782, 85803380983100, 376481393024385, 1655473716162471 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,3

COMMENTS

Needs a more precise definition.

LINKS

Table of n, a(n) for n=0..26.

R. J. Mathar, Topologically Distinct Sets of Non-intersecting Circles in the Plane, arXiv:1603.00077, 2016. See (102).

CROSSREFS

Sequence in context: A121096 A047091 A121092 * A030981 A151455 A149269

Adjacent sequences:  A281343 A281344 A281345 * A281347 A281348 A281349

KEYWORD

nonn

AUTHOR

N. J. A. Sloane, Jan 20 2017

STATUS

approved

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Last modified January 23 13:56 EST 2020. Contains 331171 sequences. (Running on oeis4.)