A378352 Decimal expansion of the volume of a (small) triakis octahedron with unit shorter edge length.

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

Offset

1,1

Comments

The (small) triakis octahedron is the dual polyhedron of the truncated cube.

Links

Table of n, a(n) for n=1..90.

Eric Weisstein's World of Mathematics, Small Triakis Octahedron.

Wikipedia, Triakis octahedron.

Formula

Equals sqrt(2) + 3/2 = A002193 + 3/2.

Equals A156035/2. - Hugo Pfoertner, Nov 24 2024

Example

2.9142135623730950488016887242096980785696718753769...

Mathematica

First[RealDigits[Sqrt[2] + 3/2, 10, 100]] (* or *)
First[RealDigits[PolyhedronData["TriakisOctahedron", "Volume"], 10, 100]]

Crossrefs

Cf. A378351 (surface area), A378353 (inradius), A201488 (midradius), A378354 (dihedral angle).

Cf. A377299 (volume of a truncated cube with unit edge).

Cf. A002193, A156035.

Sequence in context: A190142 A173995 A272868 * A074950 A346170 A113211

Adjacent sequences: A378342 A378343 A378351 * A378353 A378354 A378355

Keyword

nonn,cons,easy,new

Author

Paolo Xausa, Nov 23 2024

Status

approved