login
A274702
a(n) = number of arrangements of n circles in the affine plane in which all circles share part of their boundary with the boundary of the union of all the circles.
2
OFFSET
1,2
COMMENTS
Consider the arrangements of n circles described in A250001.
CROSSREFS
Leading diagonal of triangle A249752.
Cf. A250001.
Sequence in context: A306784 A078537 A145502 * A072444 A334807 A052596
KEYWORD
nonn,hard,more
AUTHOR
Omar E. Pol, Jul 06 2016
STATUS
approved