A371253 Number of regions 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.

1, 1, 6, 5, 26, 18, 99, 89, 270, 271, 650, 516, 1288, 1303, 2250, 2337, 4047, 3636, 6404, 6401, 9597, 9769, 14261, 13632, 20251, 20125, 27594, 27749, 37324, 35040, 49043, 49185, 63228, 63547, 80676, 79380, 101640, 102259, 125853, 126561

Offset

1,3

Comments

See A371254 for further information.

Links

Table of n, a(n) for n=1..40.

Scott R. Shannon, Image for n = 3.

Scott R. Shannon, Image for n = 4.

Scott R. Shannon, Image for n = 5.

Scott R. Shannon, Image for n = 6.

Scott R. Shannon, Image for n = 7.

Scott R. Shannon, Image for n = 8.

Scott R. Shannon, Image for n = 9.

Scott R. Shannon, Image for n = 10.

Scott R. Shannon, Image for n = 11.

Scott R. Shannon, Image for n = 12.

Scott R. Shannon, Image for n = 16.

Scott R. Shannon, Image for n = 20.

Scott R. Shannon, Image for n = 24.

Formula

a(n) = A371255(n) - A371254(n) + 1 by Euler's formula.

Crossrefs

Cf. A371254 (vertices), A371255 (edges), A371274 (k-gons), A370980 (number of circles), A371374 (complete circles), A006533, A358782, A359046, A359253, A007678.

Sequence in context: A267284 A228969 A256961 * A267743 A298155 A219931

Adjacent sequences: A371250 A371251 A371252 * A371254 A371255 A371256

Keyword

nonn

Author

Scott R. Shannon, Mar 16 2024

Status

approved