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%I #13 Mar 23 2024 21:19:05
%S 1,2,9,8,40,24,168,152,477,490,1199,912,2418,2464,4230,4464,7769,6894,
%T 12369,12400,18606,19008,27784,26376,39575,39390,54027,54432,73254,
%U 68340,96410,96800,124443,125222,159005,156168,200540,201932,248508,250120
%N Number of (curved) edges formed when n equally spaced points are placed around a circle and all pairs of points are joined by an interior arc whose radius equals the circle's radius.
%C See A371253 and A371254 for images of the circles.
%F a(n) = A371253(n) + A371254(n) - 1 by Euler's formula.
%Y Cf. A371253 (regions), A371254 (vertices), A371274 (k-gons), A135565, A358783, A359047, A359254.
%K nonn
%O 1,2
%A _Scott R. Shannon_, Mar 16 2024