A396517 Decimal expansion of 8*(2 - sqrt(2)).

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

Offset

1,1

Comments

Volume of a tricylinder, a Steinmetz solid created by the intersection of three cylinders with unit radius intersecting at right angles, with their longitudinal axes meeting at a single point.

Links

Paolo Xausa, Table of n, a(n) for n = 1..10000

Eric Weisstein's World of Mathematics, Steinmetz Solid.

Wikipedia, Steinmetz solid.

Index entries for algebraic numbers, degree 2.

Formula

Equals 8*A101465.

Equals A396518/3.

Equals the smallest root of x^2 - 32*x + 128.

Example

4.6862915010152396095864902063224153714426249969844...

Mathematica

First[RealDigits[8*(2 - Sqrt[2]), 10, 100]]

Crossrefs

Cf. A396518 (surface area).

Cf. volume of other cylinder intersections: A396519 (four cylinders), A396520 (six cylinders).

Cf. A101465.

Sequence in context: A201336 A244850 A188930 * A332331 A352421 A159576

Adjacent sequences: A396512 A396513 A396516 * A396518 A396519 A396520

Keyword

nonn,cons,easy,new

Author

Paolo Xausa, May 31 2026

Status

approved