login
This site is supported by donations to The OEIS Foundation.

 

Logo

Please make a donation to keep the OEIS running. We are now in our 55th year. In the past year we added 12000 new sequences and reached 8000 citations (which often say "discovered thanks to the OEIS"). We need to raise money to hire someone to manage submissions, which would reduce the load on our editors and speed up editing.
Other ways to donate

Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A275924 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. 23
1, 1, 1, 6, 112, 15502 (list; graph; refs; listen; history; text; internal format)
OFFSET

0,4

COMMENTS

Arrangements in A250001 that are connected, in the sense that the union of the (boundaries of the) circles is a connected set. See A250001, the main entry for this problem, for further information.

LINKS

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

Jon Wild, Figure showing relationship between A250001, A275923, A275924, and A288554 for n=3 circles

CROSSREFS

Cf. A250001, A275923, A288554-A288568.

Sequence in context: A009612 A009798 A088668 * A288561 A291917 A066931

Adjacent sequences:  A275921 A275922 A275923 * A275925 A275926 A275927

KEYWORD

nonn,more

AUTHOR

N. J. A. Sloane, Aug 29 2016, based on information supplied by Jon Wild.

EXTENSIONS

a(5) corrected by Jon Wild, Aug 31 2016

STATUS

approved

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recent
The OEIS Community | Maintained by The OEIS Foundation Inc.

License Agreements, Terms of Use, Privacy Policy. .

Last modified December 5 15:11 EST 2019. Contains 329753 sequences. (Running on oeis4.)