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 1-6 of 6 results.

A378393 Decimal expansion of the midradius of a deltoidal icositetrahedron with unit shorter edge length.

Original entry on oeis.org

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

Views

Author

Paolo Xausa, Nov 30 2024

Keywords

Comments

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

Examples

			1.5606601717798212866012665431572735589272539065327...
		

Crossrefs

Cf. A378390 (surface area), A378391 (volume), A378392 (inradius), A378394 (dihedral angle).
Cf. A285871 (midradius of a (small) rhombicuboctahedron with unit edge).

Programs

  • Mathematica
    First[RealDigits[(2 + Sqrt[18])/4, 10, 100]] (* or *)
    First[RealDigits[PolyhedronData["DeltoidalIcositetrahedron", "Midradius"], 10, 100]]

Formula

Equals (2 + 3*sqrt(2))/4 = (2 + A010474)/4.

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).

A378391 Decimal expansion of the volume of a deltoidal icositetrahedron with unit shorter edge length.

Original entry on oeis.org

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

Views

Author

Paolo Xausa, Nov 30 2024

Keywords

Comments

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

Examples

			14.9133887137863387908227981130654481094824451352...
		

Crossrefs

Cf. A378390 (surface area), A378392 (inradius), A378393 (midradius), A378394 (dihedral angle).
Cf. A343965 (volume of a (small) rhombicuboctahedron with unit edge).
Cf. A002193.

Programs

  • Mathematica
    First[RealDigits[Sqrt[122 + 71*Sqrt[2]], 10, 100]] (* or *)
    First[RealDigits[PolyhedronData["DeltoidalIcositetrahedron", "Volume"], 10, 100]]

Formula

Equals sqrt(122 + 71*sqrt(2)) = sqrt(122 + 71*A002193).

A378392 Decimal expansion of the inradius of a deltoidal icositetrahedron with unit shorter edge length.

Original entry on oeis.org

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

Views

Author

Paolo Xausa, Nov 30 2024

Keywords

Comments

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

Examples

			1.4575767431694506679193428707184970573873139019359...
		

Crossrefs

Cf. A378390 (surface area), A378391 (volume), A378393 (midradius), A378394 (dihedral angle).
Cf. A002193.

Programs

  • Mathematica
    First[RealDigits[Sqrt[39/34 + 47/(34*Sqrt[2])], 10, 100]] (* or *)
    First[RealDigits[PolyhedronData["DeltoidalIcositetrahedron", "Inradius"], 10, 100]]

Formula

Equals sqrt(39/34 + 47/(34*sqrt(2))) = sqrt(39/34 + 47/(34*A002193)).

A380704 Decimal expansion of the acute vertex angles, in radians, in a deltoidal icositetrahedron face.

Original entry on oeis.org

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

Views

Author

Paolo Xausa, Jan 31 2025

Keywords

Examples

			1.4238211361313915494455573566669046848857979902951...
		

Crossrefs

Cf. A380705 (obtuse face angle).

Programs

  • Mathematica
    First[RealDigits[ArcCos[1/2 - Sqrt[2]/4], 10, 100]]

Formula

Equals arccos(1/2 - sqrt(2)/4) = arccos(1/2 - A020765).
Equals (2*Pi - A380705)/3.

A380705 Decimal expansion of the obtuse vertex angle, in radians, in a deltoidal icositetrahedron face.

Original entry on oeis.org

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

Views

Author

Paolo Xausa, Jan 31 2025

Keywords

Examples

			2.0117218987854118285886146965582917137369448278649...
		

Crossrefs

Cf. A380704 (face acute angles).

Programs

  • Mathematica
    First[RealDigits[ArcCos[-1/4 - Sqrt[2]/8], 10, 100]]

Formula

Equals arccos(-1/4 - sqrt(2)/8) = arccos(-1/4 - A020789).
Equals 2*Pi - 3*A380704.
Showing 1-6 of 6 results.