A378388 Decimal expansion of the surface area of a tetrakis hexahedron with unit shorter edge length.

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

Offset: 2

Author

Paolo Xausa, Nov 27 2024

Keywords

• nonn
• cons
• easy

Comments

The tetrakis hexahedron is the dual polyhedron of the truncated octahedron.

Examples

			11.925695879998878380848926233233473255683297917928...
		

Links

• Paolo Xausa, Table of n, a(n) for n = 2..10000
• Eric Weisstein's World of Mathematics, Tetrakis Hexahedron.

Crossrefs

Cf. A374359 (volume - 1), A010532 (inradius*10), A179587 (midradius + 1), A378389 (dihedral angle).

Cf. A377341 (surface area of a truncated octahedron with unit edge).

Cf. A002163, A208899.

Programs

Mathematica

First[RealDigits[16*Sqrt[5]/3, 10, 100]] (* or *)
First[RealDigits[PolyhedronData["TetrakisHexahedron", "SurfaceArea"], 10, 100]]

Formula

Equals (16/3)*sqrt(5) = (16/3)*A002163 = 16*A208899.