A380700 Decimal expansion of the acute vertex angles, in radians, in a triakis tetrahedron face.

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

Offset

0,1

Links

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

Wikipedia, Triakis tetrahedron.

Formula

Equals arccos(5/6).

Equals (Pi - A380701)/2.

Example

0.58568554345715095961775753847751776620036106717164...

Mathematica

First[RealDigits[ArcCos[5/6], 10, 100]]

Crossrefs

Cf. A380701 (face obtuse angle).

Cf. A378204, A378205, A378206, A378207, A378208.

Sequence in context: A178331 A199395 A366163 * A371945 A358630 A100610

Adjacent sequences: A380697 A380698 A380699 * A380701 A380702 A380703

Keyword

nonn,cons,easy,new

Author

Paolo Xausa, Jan 30 2025

Status

approved