A381672 Decimal expansion of the isoperimetric quotient of a regular icosahedron.

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

Offset

0,1

Comments

For the definition of isoperimetric quotient of a solid, see A381671.

Links

Paolo Xausa, Table of n, a(n) for n = 0..10000

Formula

Equals Pi*phi^4/(15*sqrt(3)) = A000796*A374883/(15*A002194).

Example

0.8287977192520120215005810038129635758617830308723...

Mathematica

First[RealDigits[Pi*GoldenRatio^4/(15*Sqrt[3]), 10, 100]]

Crossrefs

Cf. A273637 (sphericity).

Cf. isoperimetric quotient of other Platonic solids: A019673 (cube), A073010 (octahedron), A374772 (dodecahedron), A381671 (tetrahedron).

Cf. A000796, A002194, A374883.

Sequence in context: A390110 A211269 A278809 * A306617 A278261 A296301

Adjacent sequences: A381669 A381670 A381671 * A381673 A381674 A381675

Keyword

nonn,cons,easy

Author

Paolo Xausa, Mar 03 2025

Status

approved