A380982 Decimal expansion of the long/short edge length ratio of a disdyakis triacontahedron.

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

Offset

1,2

Links

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

Polytope Wiki, Disdyakis triacontahedron.

Eric Weisstein's World of Mathematics, Disdyakis Triacontahedron.

Wikipedia, Disdyakis triacontahedron.

Index entries for algebraic numbers, degree 2.

Formula

Equals 1/sqrt(5) + 7/5 = A020762 + 7/5.

Minimal polynomial: 25*x^2 - 70*x + 44. - Amiram Eldar, Jun 09 2026

Example

1.8472135954999579392818347337462552470881236719223...

Mathematica

First[RealDigits[7/5 + 1/Sqrt[5], 10, 100]] (* Paolo Xausa, Feb 10 2025 *)

Crossrefs

Cf. A380981 (medium/short edge length ratio).

Cf. A020762, A379388, A379708, A379709, A379710, A379711, A380940, A380941, A380942.

Apart from leading digits the same as A176453, A134974 and A010476.

Sequence in context: A195346 A388821 A096427 * A176453 A388905 A257775

Adjacent sequences: A380979 A380980 A380981 * A380983 A380984 A380985

Keyword

nonn,cons,easy

Author

Paolo Xausa, Feb 10 2025

Status

approved