A343864 Decimal expansion of 12*sqrt(3)/(3+sqrt(5)).

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

Offset

1,1

Comments

Surface area to volume ratio of an icosahedron with unit side length.

Links

Table of n, a(n) for n=1..93.

Wikipedia, Surface-area-to-volume ratio.

Index entries for algebraic numbers, degree 4.

Formula

Minimal polynomial: x^4 - 756*x^2 + 11664. - Amiram Eldar, May 26 2026

Example

3.9695072294976449862092208742056524...

Mathematica

RealDigits[12 Sqrt[3]/(3 + Sqrt[5]), 10, 100] // Flatten

Prog

(PARI) 12*sqrt(3)/(3+sqrt(5)) \\ Charles R Greathouse IV, May 18 2026

Crossrefs

Cf. A343745.

Sequence in context: A349850 A331063 A199738 * A309613 A189272 A349403

Adjacent sequences: A343861 A343862 A343863 * A343865 A343866 A343867

Keyword

nonn,cons

Author

Wesley Ivan Hurt, May 03 2021

Status

approved