A380702 Decimal expansion of the acute vertex angles, in radians, in a (small) triakis octahedron face.

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

Offset

0,1

Links

Paolo Xausa, Table of n, a(n) for n = 0..10000

Wikipedia, Triakis octahedron.

Formula

Equals arccos(1/2 + sqrt(2)/4) = arccos(1/2 + A020765).

Equals (Pi - A380703)/2.

Equals A361601/2. - Hugo Pfoertner, Jan 30 2025

Example

0.54802840762031274453086328282062867847971236365920...

Mathematica

First[RealDigits[ArcCos[1/2 + Sqrt[2]/4], 10, 100]]

Crossrefs

Cf. A380703 (face obtuse angle).

Cf. A020765, A361601, A378351, A378352, A378353, A378354.

Sequence in context: A105665 A019129 A019208 * A051553 A203139 A184085

Adjacent sequences: A380699 A380700 A380701 * A380703 A380704 A380705

Keyword

nonn,cons,easy

Author

Paolo Xausa, Jan 30 2025

Status

approved