A378206 Decimal expansion of the inradius of a triakis tetrahedron with unit shorter edge length.

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

Offset

0,1

Comments

The triakis tetrahedron is the dual polyhedron of the truncated tetrahedron.

Links

Table of n, a(n) for n=0..89.

Index entries for algebraic numbers, degree 2.

Formula

Equals 5/(2*sqrt(22)) = 5/A010539.

Example

0.53300179088902608574609433108459844097593504016042...

Mathematica

First[RealDigits[5/Sqrt[88], 10, 100]] (* or *)
First[RealDigits[PolyhedronData["TriakisTetrahedron", "Inradius"], 10, 100]]

Crossrefs

Cf. A378204 (surface area), A378205 (volume), A378207 (midradius), A378208 (dihedral angle).

Cf. A010539.

Sequence in context: A262225 A330092 A064812 * A282469 A216998 A346469

Adjacent sequences: A378203 A378204 A378205 * A378207 A378208 A378209

Keyword

nonn,cons,easy

Author

Paolo Xausa, Nov 21 2024

Status

approved