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 1-9 of 9 results.

A379709 Decimal expansion of the volume of a disdyakis triacontahedron with unit shorter edge length.

Original entry on oeis.org

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

Views

Author

Paolo Xausa, Dec 31 2024

Keywords

Comments

The disdyakis triacontahedron is the dual polyhedron of the truncated icosidodecahedron (great rhombicosidodecahedron).

Examples

			84.1819754400481313518959942929339817444032991207...
		

Crossrefs

Cf. A379708 (surface area), A379710 (inradius), A379388 (midradius), A379711 (dihedral angle).
Cf. A377797 (volume of a truncated icosidodecahedron (great rhombicosidodecahedron) with unit edge length).
Cf. A002163.

Programs

  • Mathematica
    First[RealDigits[Sqrt[88590 + 39612*Sqrt[5]]/5, 10, 100]] (* or *)
    First[RealDigits[PolyhedronData["DisdyakisTriacontahedron", "Volume"], 10, 100]]

Formula

Equals sqrt(88590 + 39612*sqrt(5))/5 = sqrt(88590 + 39612*A002163)/5.

A379710 Decimal expansion of the inradius of a disdyakis triacontahedron with unit shorter edge length.

Original entry on oeis.org

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

Views

Author

Paolo Xausa, Dec 31 2024

Keywords

Comments

The disdyakis triacontahedron is the dual polyhedron of the truncated icosidodecahedron (great rhombicosidodecahedron).

Examples

			2.679969340204835578579553327459806767085423038168...
		

Crossrefs

Cf. A379708 (surface area), A379709 (volume), A379388 (midradius), A379711 (dihedral angle).
Cf. A002163.

Programs

  • Mathematica
    First[RealDigits[Sqrt[3477/964 + 7707/(964*Sqrt[5])], 10, 100]] (* or *)
    First[RealDigits[PolyhedronData["DisdyakisTriacontahedron", "Inradius"], 10, 100]]

Formula

Equals sqrt(3477/964 + 7707/(964*sqrt(5))) = sqrt(3477/964 + 7707/(964*A002163)).

A379711 Decimal expansion of the dihedral angle, in radians, between any two adjacent faces in a disdyakis triacontahedron.

Original entry on oeis.org

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

Views

Author

Paolo Xausa, Dec 31 2024

Keywords

Comments

The disdyakis triacontahedron is the dual polyhedron of the truncated icosidodecahedron (great rhombicosidodecahedron).

Examples

			2.8778366104612242809434504548179917754749428665406...
		

Crossrefs

Cf. A379708 (surface area), A379709 (volume), A379710 (inradius), A379388 (midradius).
Cf. A344075, A377995 and A377996 (dihedral angles of a truncated icosidodecahedron (great rhombicosidodecahedron)).
Cf. A002163.

Programs

  • Mathematica
    First[RealDigits[ArcCos[(-179 - 24*Sqrt[5])/241], 10, 100]] (* or *)
    First[RealDigits[First[PolyhedronData["DisdyakisTriacontahedron", "DihedralAngles"]], 10, 100]]

Formula

Equals arccos((-179 - 24*sqrt(5))/241) = arccos((-179 - 24*A002163)/241).

A380940 Decimal expansion of the smallest vertex angle, in radians, in a disdyakis triacontahedron face.

Original entry on oeis.org

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

Views

Author

Paolo Xausa, Feb 08 2025

Keywords

Comments

A disdyakis triacontahedron face is a scalene triangle with three acute angles.

Examples

			0.57194925611938685598415462715533824150730405467310...
		

Crossrefs

Cf. A380941 (middle face angle), A380942 (face largest face angle).

Programs

  • Mathematica
    First[RealDigits[ArcCos[(2 + 5*GoldenRatio)/12], 10, 100]]

Formula

Equals arccos((2 + 5*A001622)/12).
Equals Pi - A380941 - A380942.

A380941 Decimal expansion of the middle vertex angle, in radians, in a disdyakis triacontahedron face.

Original entry on oeis.org

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

Views

Author

Paolo Xausa, Feb 08 2025

Keywords

Comments

A disdyakis triacontahedron face is a scalene triangle with three acute angles.

Examples

			1.016443446896330150160097551517069643637928892906...
		

Crossrefs

Cf. A380940 (smallest face angle), A380942 (largest face angle).

Programs

  • Mathematica
    First[RealDigits[ArcCos[(17 - 4*GoldenRatio)/20], 10, 100]]

Formula

Equals arccos((17 - 4*A001622)/20).
Equals Pi - A380940 - A380942.

A380942 Decimal expansion of the largest vertex angle, in radians, in a disdyakis triacontahedron face.

Original entry on oeis.org

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

Views

Author

Paolo Xausa, Feb 09 2025

Keywords

Comments

A disdyakis triacontahedron face is a scalene triangle with three acute angles.

Examples

			1.5531999505740762323183912046070949990519364517956...
		

Crossrefs

Cf. A380940 (smallest face angle), A380941 (middle face angle).

Programs

  • Mathematica
    First[RealDigits[ArcCos[(7 - 4*GoldenRatio)/30], 10, 100]]

Formula

Equals arccos((7 - 4*A001622)/30).
Equals Pi - A380940 - A380941.

A380981 Decimal expansion of the medium/short edge length ratio of a disdyakis triacontahedron.

Original entry on oeis.org

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

Views

Author

Paolo Xausa, Feb 10 2025

Keywords

Examples

			1.57082039324993690892275210061938287063218550788...
		

Crossrefs

Cf. A380982 (long/short edge length ratio).
Apart from leading digits the same as A176015, A134976 and A010499.

Programs

  • Mathematica
    First[RealDigits[3/10*(3 + Sqrt[5]), 10, 100]]

Formula

Equals (3/10)*(3 + sqrt(5)) = (3/10)*(3 + A002163).
Equals A176015 + 2/5.

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

Original entry on oeis.org

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

Views

Author

Paolo Xausa, Feb 10 2025

Keywords

Examples

			1.8472135954999579392818347337462552470881236719223...
		

Crossrefs

Cf. A380981 (medium/short edge length ratio).
Apart from leading digits the same as A176453, A134974 and A010476.

Programs

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

Formula

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

A382012 Decimal expansion of the isoperimetric quotient of a disdyakis triacontahedron.

Original entry on oeis.org

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

Views

Author

Paolo Xausa, Mar 20 2025

Keywords

Comments

For the definition of isoperimetric quotient of a solid, references and links, see A381684.
The disdyakis triacontahedron is the Catalan solid with the highest isoperimetric quotient.

Examples

			0.95776502384780769076187408953240617790783343820517...
		

Crossrefs

Cf. A379708 (surface area), A379709 (volume).

Programs

  • Mathematica
    First[RealDigits[Pi*Root[13997521*#^4 - 1302278*#^2 + 121 &, 4], 10, 100]]

Formula

Equals 36*Pi*A379709^2/(A379708^3).
Equals Pi*r = A000796*r, where r is the largest root of 13997521*x^4 - 1302278*x^2 + 121.
Showing 1-9 of 9 results.