A386412 Decimal expansion of the surface area of an augmented truncated tetrahedron with unit edge.

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

Offset

2,2

Comments

The augmented truncated tetrahedron is Johnson solid J_65.

Links

Paolo Xausa, Table of n, a(n) for n = 2..10000

Wikipedia, Augmented truncated tetrahedron.

Formula

Equals 3 + 13*sqrt(3)/2 = 3 + 13*A010527.

Equals the largest root of 4*x^2 - 24*x - 471.

Example

14.258330249197702407928401219788170385128234149767...

Mathematica

First[RealDigits[3 + 13*Sqrt[3]/2, 10, 100]] (* or *)
First[RealDigits[PolyhedronData["J65", "SurfaceArea"], 10, 100]]

Crossrefs

Cf. A386411 (volume).

Cf. A010527.

Sequence in context: A266626 A159979 A198233 * A169850 A371904 A112962

Adjacent sequences: A386409 A386410 A386411 * A386413 A386414 A386415

Keyword

nonn,cons,easy

Author

Paolo Xausa, Jul 21 2025

Status

approved