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A371375
Place n equally space points around the circumference of a circle and then, for each pair of points, draw two distinct circles, whose radii are the same as the first circle, such that both points lie on their circumferences. The sequence gives the total number of (curved) edges formed.
9
1, 2, 12, 12, 75, 66, 350, 360, 1071, 1150, 2684, 2148, 5603, 5950, 10110, 10928, 18309, 16830, 29564, 30500, 44961, 46882, 66746, 64872, 95125, 97786, 131112, 135156, 177567, 169770, 235042, 240928, 304359, 312086, 389340, 388764, 491175, 503158, 610662, 624280, 752145, 749742, 917276
OFFSET
1,2
COMMENTS
See A371373 and A371374 for images of the graphs.
FORMULA
a(n) = A371373(n) + A371374(n) - 1 by Euler's formula.
CROSSREFS
Cf. A371373 (vertices), A371374 (regions), A371376 (k-gons), A371377 (vertex crossings), A371255, A135565, A358783, A359047.
Sequence in context: A045895 A251421 A226393 * A198532 A198477 A075178
KEYWORD
nonn
AUTHOR
Scott R. Shannon, Mar 20 2024
STATUS
approved