A386461 Decimal expansion of the surface area of a biaugmented truncated cube with unit edges.

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

Offset

2,1

Comments

The biaugmented truncated cube is Johnson solid J_67.

Links

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

Wikipedia, Biaugmented truncated cube.

Formula

Equals 2*(9 + 4*sqrt(2) + 2*sqrt(3)) = 2*(9 + A010487 + A010469) = 18 + A377342 + A010502.

Equals the largest root of x^4 - 72*x^3 + 1592*x^2 - 10656*x - 2672.

Example

36.241911729260269564523295159701074096328596018257...

Mathematica

First[RealDigits[18 + 8*Sqrt[2] + Sqrt[48], 10, 100]] (* or *)
First[RealDigits[PolyhedronData["J67", "SurfaceArea"], 10, 100]]

Crossrefs

Cf. A010524 (volume - 9).

Cf. A010469, A010487, A010502, A377342, A385535, A386460.

Sequence in context: A319674 A372696 A021738 * A016614 A019769 A092948

Adjacent sequences: A386458 A386459 A386460 * A386462 A386463 A386464

Keyword

nonn,cons,easy

Author

Paolo Xausa, Jul 23 2025

Status

approved