A378351 Decimal expansion of the surface area of a (small) triakis octahedron with unit shorter edge length.

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

Offset

2,3

Comments

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

Links

Table of n, a(n) for n=2..91.

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

Wikipedia, Triakis octahedron.

Formula

Equals 3*sqrt(7 + 4*sqrt(2)) = 3*sqrt(7 + A010487).

Example

10.672941873983546705150008922490160564590104237715...

Mathematica

First[RealDigits[3*Sqrt[7 + Sqrt[32]], 10, 100]] (* or *)
First[RealDigits[PolyhedronData["TriakisOctahedron", "SurfaceArea"], 10, 100]]

Crossrefs

Cf. A378352 (volume), A378353 (inradius), A201488 (midradius), A378354 (dihedral angle).

Cf. A377298 (surface area of a truncated cube with unit edge).

Cf. A010487.

Sequence in context: A308039 A316165 A267251 * A259526 A108664 A160155

Adjacent sequences: A378341 A378342 A378343 * A378352 A378353 A378354

Keyword

nonn,cons,easy,new

Author

Paolo Xausa, Nov 23 2024

Status

approved