cp's OEIS Frontend

This is a front-end for the Online Encyclopedia of Integer Sequences, made by Christian Perfect. The idea is to provide OEIS entries in non-ancient HTML, and then to think about how they're presented visually. The source code is on GitHub.

Showing 1-4 of 4 results.

A378390 Decimal expansion of the surface area of a deltoidal icositetrahedron with unit shorter edge length.

Original entry on oeis.org

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

Views

Author

Paolo Xausa, Nov 29 2024

Keywords

Comments

The deltoidal icositetrahedron is the dual polyhedron of the (small) rhombicuboctahedron.

Examples

			30.694895724031009590770314784050673387965107463161...
		

Crossrefs

Cf. A378391 (volume), A378392 (inradius), A378393 (midradius), A378394 (dihedral angle).
Cf. A343964 (surface area of a (small) rhombicuboctahedron with unit edge).
Cf. A010466.

Programs

  • Mathematica
    First[RealDigits[6*Sqrt[29 - Sqrt[8]], 10, 100]] (* or *)
    First[RealDigits[PolyhedronData["DeltoidalIcositetrahedron", "SurfaceArea"], 10, 100]]

Formula

Equals 6*sqrt(29 - 2*sqrt(2)) = 6*sqrt(29 - A010466).

A343965 Decimal expansion of 4 + 10*sqrt(2)/3.

Original entry on oeis.org

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

Views

Author

Wesley Ivan Hurt, May 05 2021

Keywords

Comments

Volume of a rhombicuboctahedron with unit edge length.
Apart from the leading digit and offset the same as A131594. - R. J. Mathar, May 07 2021

Examples

			8.7140452079103168293389624140323269285655729...
		

Crossrefs

Cf. A343964 (rhombicuboctahedron surface area).

Programs

  • Magma
    SetDefaultRealField(RealField(100)); 4+10*Sqrt(2)/3;
  • Mathematica
    RealDigits[N[4 + 10*Sqrt[2]/3, 100]][[1]] (* Wesley Ivan Hurt, Nov 12 2022 *)

A381688 Decimal expansion of the isoperimetric quotient of a (small) rhombicuboctahedron.

Original entry on oeis.org

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

Views

Author

Paolo Xausa, Mar 04 2025

Keywords

Comments

For the definition of isoperimetric quotient of a solid, references and links, see A381684.

Examples

			0.8684680457998683969444644014889968511341210788731...
		

Crossrefs

Cf. A343964 (surface area), A343965 (volume).

Programs

  • Mathematica
    First[RealDigits[4*Pi*(43 + 30*Sqrt[2])/(9 + Sqrt[3])^3, 10, 100]]

Formula

Equals 36*Pi*A343965^2/(A343964^3).
Equals 4*Pi*(43 + 30*sqrt(2))/((9 + sqrt(3))^3) = 4*A000796*(43 + 30*A002193)/((9 + A002194)^3).

A343966 Decimal expansion of (4/3)*(4*sqrt(2)-5).

Original entry on oeis.org

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

Views

Author

Wesley Ivan Hurt, May 05 2021

Keywords

Comments

The optimal packing fraction of a rhombicuboctahedron is (4/3)*(4*sqrt(2)-5).

Examples

			0.87580566598984026027567319578505641903825...
		

Crossrefs

Cf. A343964 (rhombicuboctahedron surface area).
Cf. A343965 (rhombicuboctahedron volume).

Programs

  • Magma
    SetDefaultRealField(RealField(100)); (4/3)*(4*Sqrt(2)-5);
  • Mathematica
    RealDigits[N[(4/3)*(4*Sqrt[2] - 5), 100]][[1]] (* Wesley Ivan Hurt, Nov 12 2022 *)
Showing 1-4 of 4 results.