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A362234
Number of regions 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 when each pair of points is connected by a circle and where the points lie at the ends of the circles' diameter.
5
32, 372, 1804, 5772, 14660, 30816, 58232, 100080, 161700, 249200, 368384
OFFSET
1,1
COMMENTS
A circle is constructed for every pair of the 1 + 4n points, the two points lying at the ends of a diameter of the circle. The number of distinct circles constructed from the points is A139275(n).
No formula for a(n) is currently known.
LINKS
Scott R. Shannon, Image for n = 1.
Scott R. Shannon, Image for n = 2.
Scott R. Shannon, Image for n = 3.
Scott R. Shannon, Image for n = 4.
FORMULA
a(n) = A362235(n) - A362233(n) + 1 by Euler's formula.
CROSSREFS
Cf. A362233 (vertices), A362235 (edges), A362236 (k-gons), A139275 (distinct circles), A353782, A359933.
Sequence in context: A191901 A191489 A055752 * A250170 A125420 A163690
KEYWORD
nonn,more
AUTHOR
Scott R. Shannon, Apr 13 2023
STATUS
approved