A288561 Number of connected arrangements of n pseudo-circles in the affine plane, in the sense that the union of the boundaries of the pseudo-circles is a connected set.

1, 1, 6, 112, 15528

Offset

0,3

Comments

Arrangements in A288559 that are connected, in the sense that the union of the (boundaries of the) pseudo-circles is a connected set.

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..4.

Crossrefs

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

Sequence in context: A341478 A088668 A275924 * A291917 A066931 A324669

Adjacent sequences: A288558 A288559 A288560 * A288562 A288563 A288564

Keyword

nonn,more

Author

N. J. A. Sloane, Jun 13 2017, based on information supplied by Jon Wild on Aug 31 2016.

Status

approved