A375190 Decimal expansion of the circumradius of a regular 11-gon with unit side length.

1, 7, 7, 4, 7, 3, 2, 7, 6, 6, 4, 4, 2, 1, 1, 1, 6, 6, 2, 8, 5, 6, 8, 3, 1, 9, 6, 1, 1, 6, 8, 9, 7, 5, 8, 4, 6, 1, 0, 5, 3, 7, 6, 3, 8, 2, 1, 2, 3, 0, 5, 1, 0, 6, 9, 5, 5, 2, 5, 8, 2, 9, 4, 3, 1, 5, 7, 3, 0, 0, 4, 9, 5, 8, 2, 6, 1, 6, 6, 9, 5, 0, 0, 1, 7, 7, 9, 5, 9, 9

Offset

1,2

Links

Paolo Xausa, Table of n, a(n) for n = 1..10000

Eric Weisstein's World of Mathematics, Regular Polygon.

Wikipedia, Regular polygon.

Formula

Equals csc(Pi/11)/2.

Equals 1/(2*sin(Pi/11)) = 1/A272489.

Equals A375191/cos(Pi/11).

Equals A375191 + A375192.

Example

1.774732766442111662856831961168975846105376382123...

Mathematica

First[RealDigits[Csc[Pi/11]/2, 10, 100]]

Crossrefs

Cf. A375191 (apothem), A375192 (sagitta), A256854 (area).

Cf. circumradius of other polygons with unit side length: A020760 (triangle), A010503 (square), A300074 (pentagon), A374957 (heptagon), A285871 (octagon), A375151 (9-gon), A001622 (10-gon), A188887 (12-gon).

Cf. A272489.

Sequence in context: A201517 A010513 A225402 * A081824 A199083 A109939

Adjacent sequences: A375187 A375188 A375189 * A375191 A375192 A375193

Keyword

nonn,cons,easy

Author

Paolo Xausa, Aug 04 2024

Status

approved