A385506 Decimal expansion of the volume of a triaugmented triangular prism with unit edge.

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

Offset: 1

Author

Paolo Xausa, Jul 01 2025

Keywords

• nonn
• cons
• easy

Comments

The triaugmented triangular prism is Johnson solid J_51.

Examples

			1.140119483078766847782705947481317131020537251141...
		

Links

• Paolo Xausa, Table of n, a(n) for n = 1..10000
• Wikipedia, Triaugmented triangular prism.

Crossrefs

Cf. A097715 (surface area).

Cf. A002194, A010466, A010503, A120011, A385505.

Programs

Mathematica

First[RealDigits[(Sqrt[8] + Sqrt[3])/4, 10, 100]] (* or *)
First[RealDigits[PolyhedronData["J51", "Volume"], 10, 100]]

Formula

Equals 1/sqrt(2) + sqrt(3)/4 = A010503 + A120011 = (A010466 + A002194)/4.

Equals the largest root of 256*x^4 - 352*x^2 + 25.