%I #21 Jun 15 2017 13:51:03
%S 1,1,2,11,156,16756
%N Number of connected arrangements of n circles in the affine plane, in the sense that the union of the solid circles is a connected set.
%C Arrangements in A250001 that are connected (in the sense that the union of the solid circles is a connected set). See A250001, the main entry for this problem, for further information.
%C Is this also 1 together with column 1 of A285996? - _Omar E. Pol_, May 28 2017
%H Jon Wild, <a href="/A275923/a275923.png">Figure showing relationship between A250001, A275923, A275924, and A288554 for n=3 circles</a>
%Y Cf. A250001, A275924, A288554-A288568.
%K nonn,more
%O 0,3
%A _N. J. A. Sloane_, Aug 29 2016, based on information supplied by _Jon Wild_.
%E a(5) from _Jon Wild_, Aug 31 2016
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