A394534 Decimal expansion of the volume of a uniform octagonal antiprism with unit edges.

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

Offset

1,1

Links

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

David I. McCooey, Octagonal Antiprism.

Polytope Wiki, Octagonal antiprism.

Eric Weisstein's World of Mathematics, Antiprism.

Wikipedia, Antiprism.

Formula

Equals (2/3)*sqrt(2*(sqrt(2) + sqrt(103*sqrt(2) + 146) + 2)) = (2/3)*sqrt(2*(A002193 + sqrt(103*A002193 + 146) + 2)).

Equals the largest real root of 6561*x^8 - 46656*x^6 - 1410048*x^4 + 1511424*x^2 - 8192.

Example

4.2679567504571366707904363506533419312469857373291...

Mathematica

First[RealDigits[2*Sqrt[2*(2 + Sqrt[2] + Sqrt[146 + 103*Sqrt[2]])]/3, 10, 100]] (* or *)
First[RealDigits[PolyhedronData["OctagonalAntiprism", "Volume"], 10, 100]]

Crossrefs

Cf. A394535 (surface area), A394536 (midradius), A394537 (circumradius), A394538 (height).

Cf. A387320, A387323 (dihedral angles).

Cf. A002193.

Sequence in context: A256568 A138947 A083412 * A086399 A105365 A077157

Adjacent sequences: A394531 A394532 A394533 * A394535 A394536 A394537

Keyword

nonn,cons,easy

Author

Paolo Xausa, Apr 04 2026

Status

approved