A378353 Decimal expansion of the inradius of a (small) triakis octahedron with unit shorter edge length.

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

Offset: 0

Author

Paolo Xausa, Nov 23 2024

Keywords

• nonn
• cons
• easy

Comments

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

Examples

			0.81914066340325716171549134573565316624155520306132...
		

Crossrefs

Cf. A378351 (surface area), A378352 (volume), A201488 (midradius), A378354 (dihedral angle).

Cf. A010487.

Programs

Mathematica

First[RealDigits[Sqrt[23/68 + Sqrt[32]/17], 10, 100]] (* or *)
First[RealDigits[PolyhedronData["TriakisOctahedron", "Inradius"], 10, 100]]

Formula

Equals sqrt(23/68 + 4*sqrt(2)/17) = sqrt(23/68 + A010487/17).