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%I #57 Mar 20 2023 10:39:35
%S 101,1145,5001,13753,34497,72185,135157,224321
%N Number of vertices among all distinct circles that can be constructed from a point on the origin and n equally spaced points on each of the +x,-x,+y,-y coordinates axes using only a compass.
%C A circle is constructed for every pair of the 1 + 4n points, the first point defines the circle's center while the second the radius distance. The number of distinct circles constructed from the points is A361622(n).
%C No formula for a(n) is currently known.
%H Scott R. Shannon, <a href="/A354605/a354605.jpg">Image for n = 1</a>.
%H Scott R. Shannon, <a href="/A354605/a354605_1.jpg">Image for n = 2</a>.
%H Scott R. Shannon, <a href="/A354605/a354605_3.jpg">Image for n = 3</a>.
%F a(n) = A356358 - A353782(n) + 1 by Euler's formula.
%Y Cf. A353782 (regions), A356358 (edges), A361623 (k-gons), A361622 (distinct circles), A359932, A359859, A359252, A359569, A331702.
%K nonn,more
%O 1,1
%A _Scott R. Shannon_, Mar 13 2023