A374957 - OEIS

A374957

Decimal expansion of the circumradius of a regular heptagon with unit side length.

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

(list; constant; graph; refs; listen; history; text; internal format)

OFFSET

1,3

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/7)/2 = A121598/2.

Equals 1/(2*sin(Pi/7)) = 1/A272487.

Equals A374971/cos(Pi/7) = A374971/A073052.

Equals A374972 + A374971.

EXAMPLE

1.15238243548124325262057511177342755672225094380...

MATHEMATICA

First[RealDigits[Csc[Pi/7]/2, 10, 100]]

CROSSREFS

Cf. A374971 (apothem), A374972 (sagitta), A178817 (area).

Cf. circumradius of other polygons with unit side length: A020760 (triangle), A010503 (square), A300074 (pentagon), A285871 (octagon), A375151 (9-gon), A001622 (10-gon), A375190 (11-gon), A188887 (12-gon).

Cf. A073052, A121598, A272487.

Sequence in context: A364456 A353617 A133746 * A176319 A376913 A377088

Adjacent sequences: A374954 A374955 A374956 * A374958 A374959 A374960

KEYWORD

nonn,cons,easy

AUTHOR

Paolo Xausa, Jul 26 2024

STATUS

approved