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A288567 Number of connected arrangements of n circles in the affine plane, in the sense that the union of the boundaries of the circles is a connected set and every circle intersects all the other circles. 0
1, 1, 1, 3, 21, 980 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,4

COMMENTS

These counts have been reduced for mirror symmetry.

See A250001, the main entry for this problem, for further information.

LINKS

Table of n, a(n) for n=0..5.

CROSSREFS

Cf. A250001, A275923, A275924, A288554-A288568.

Sequence in context: A176430 A327037 A144621 * A288568 A111433 A111435

Adjacent sequences:  A288564 A288565 A288566 * A288568 A288569 A288570

KEYWORD

nonn,more

AUTHOR

N. J. A. Sloane, Jun 13 2017, based on information supplied by Jon Wild.

STATUS

approved

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Last modified December 1 22:24 EST 2020. Contains 338858 sequences. (Running on oeis4.)