A389491 Decimal expansion of the largest dihedral angle, in radians, in an augmented pentagonal prism (Johnson solid J_52).

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

Offset

1,1

Comments

This is the dihedral angle between a triangular face and a square face.

Also the analogous dihedral angle in a biaugmented pentagonal prism (Johnson solid J_53).

Links

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

Polytope Wiki, Augmented pentagonal prism.

Polytope Wiki, Biaugmented pentagonal prism.

Wikipedia, Augmented pentagonal prism.

Wikipedia, Biaugmented pentagonal prism.

Formula

Equals arctan(sqrt(2)) + (3/5)*Pi = A195696 + A228719.

Example

2.840272210278385221241443132483459484761716334635...

Mathematica

First[RealDigits[ArcTan[Sqrt[2]] + 3/5*Pi, 10, 100]] (* or *)
First[RealDigits[Max[PolyhedronData["J52", "DihedralAngles"]], 10, 100]]

Crossrefs

Cf. other J_52 dihedral angles: A019669, A156546, A195702, A228719.

Cf. A385509 (J_52 volume), A385510 (J_52 surface area).

Cf. A195696.

Sequence in context: A068565 A391867 A092042 * A158934 A021356 A030345

Adjacent sequences: A389488 A389489 A389490 * A389492 A389493 A389494

Keyword

nonn,cons,easy

Author

Paolo Xausa, Oct 07 2025

Status

approved