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.

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A179637 Decimal expansion of the surface area of pentagonal rotunda with edge length 1.

Original entry on oeis.org

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

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Author

Keywords

Comments

Pentagonal rotunda: 20 vertices, 35 edges, and 17 faces.

Examples

			22.3472002653941282767984141581886130738180135134316226129799763167102...
		

Crossrefs

Programs

  • Mathematica
    RealDigits[N[Sqrt[5*(145+58*Sqrt[5]+2*Sqrt[30*(65+29*Sqrt[5])])]/2,200]]

Formula

Digits of sqrt(5*(145+58*sqrt(5)+2*sqrt(30*(65+29*sqrt(5)))))/2.

Extensions

Offset corrected by R. J. Mathar, Aug 15 2010

A185093 Decimal expansion of the volume of small rhombicosidodecahedron with edge = 1.

Original entry on oeis.org

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

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Author

Keywords

Comments

Small Rhombicosidodecahedron: 62 faces, 60 vertices, and 120 edges.
Surface Area = 30+sqrt(30*(10+3*sqrt(5)+sqrt(75+30*sqrt(5)))) = 59.30598284491...
Circumradius = sqrt(11+4*sqrt(5))/2 = 2.23295050941569004950041538324968277293...
Midradius = sqrt(10+4*sqrt(5))/2 = 2.17625089948282151110005286599776788019807...
Quadratic number with denominator 3 and minimal polynomial 9x^2 - 360x - 605. - Charles R Greathouse IV, Apr 25 2016

Examples

			41.6153237824979670652886787977356702759259774762447486679520...
		

Crossrefs

Programs

  • Mathematica
    RealDigits[N[20 + (29*Sqrt[5])/3, 200]][[1]]
    RealDigits[PolyhedronData["Rhombicosidodecahedron","Volume"],10,100][[1]] (* Harvey P. Dale, Aug 04 2025 *)
  • PARI
    29*sqrt(5)/3+20 \\ Charles R Greathouse IV, Oct 01 2012

Extensions

Offset changed by Georg Fischer, Jul 29 2021

A339259 Decimal expansion of the volume of the regular icosahedron inscribed in the unit sphere.

Original entry on oeis.org

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

Views

Author

Hugo Pfoertner, Nov 29 2020

Keywords

Examples

			2.536150710120409525643838222345019049081863024335333926526148385147...
		

Crossrefs

Cf. A118273 (cube), A122553 (regular octahedron), A363437 (regular tetrahedron), A363438 (regular dodecahedron).

Programs

  • Mathematica
    RealDigits[4 * Sqrt[GoldenRatio + 2]/3, 10, 120][[1]] (* Amiram Eldar, Jun 02 2023 *)
  • PARI
    4/3*sqrt(2+(1+sqrt(5))/2)

Formula

Equals 4*sqrt(2 + phi)/3 where phi = A001622.
Equals A102208 / A019881 ^ 3. - Amiram Eldar, Jun 02 2023

A179589 Decimal expansion of the circumradius of square cupola with edge length 1.

Original entry on oeis.org

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

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Author

Keywords

Comments

Square cupola: 12 vertices, 20 edges, and 10 faces.

Examples

			1.398966325965906702031540539431998764673522563866238879930...
		

Crossrefs

Programs

  • Mathematica
    RealDigits[N[Sqrt[5+2*Sqrt[2]]/2,200]]

Formula

Digits of sqrt(5+2*sqrt(2))/2.

A179638 Decimal expansion of the volume of gyroelongated square pyramid with edge length 1.

Original entry on oeis.org

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

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Author

Keywords

Comments

Gyroelongated square pyramid: 9 vertices, 20 edges, and 13 faces.

Examples

			1.19270224223223255906019842837725158155262551828862015707793142188822...
		

Crossrefs

Programs

  • Mathematica
    RealDigits[N[(Sqrt[2]+2*Sqrt[4+3*Sqrt[2]])/6,200]]

Formula

Digits of (sqrt(2)+2 sqrt(4+3 sqrt(2)))/6.

A071402 Rounded volume of a regular icosahedron with edge length n.

Original entry on oeis.org

0, 2, 17, 59, 140, 273, 471, 748, 1117, 1590, 2182, 2904, 3770, 4793, 5987, 7363, 8936, 10719, 12724, 14964, 17454, 20205, 23231, 26545, 30160, 34089, 38345, 42942, 47893, 53209, 58906, 64995, 71490, 78404, 85749, 93540, 101789, 110509
Offset: 0

Views

Author

Rick L. Shepherd, May 29 2002

Keywords

Comments

The printed reference given shows in a table on p. 10 that Volume is "2.18170a^3" (a is edge). Both PARI (see Example here) and a handheld calculator show that 2.18169 is correct for a 5-decimal-place approximation.

Examples

			a(6)=471 because round(6^3*(3 + sqrt(5))*5/12) = round(216*2.181694990...) = round(471.24...) = 471.
		

References

  • S. Selby, editor, CRC Basic Mathematical Tables, CRC Press, 1970, pp. 10-11.

Crossrefs

Cf. A000578 (cube), A071399 (tetrahedron), A071400 (octahedron), A071401 (dodecahedron), A071398 (total surface area of icosahedron).
Cf. A102208 ((3+Sqrt(5)) * 5/12).

Programs

  • Magma
    [Round(n^3 * (3+Sqrt(5)) * 5/12): n in [0..50]]; // Vincenzo Librandi, May 21 2011
  • PARI
    for(n=0,100,print1(round(n^3*(3+sqrt(5))*5/12),","))
    

Formula

a(n) = round(n^3 * (3+sqrt(5)) * 5/12).

A179593 Decimal expansion of the volume of pentagonal rotunda with edge length 1.

Original entry on oeis.org

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

Views

Author

Keywords

Comments

Pentagonal rotunda: 20 vertices, 35 edges, and 17 faces.

Examples

			6.91776296812470206991299603070264133354087600944966144271710443099823...
		

Crossrefs

Programs

  • Mathematica
    RealDigits[N[(45+17*Sqrt[5])/12,200]]

Formula

Digits of (45+17*sqrt(5))/12.

A179592 Decimal expansion of the circumradius of pentagonal cupola with edge length 1.

Original entry on oeis.org

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

Views

Author

Keywords

Comments

Pentagonal cupola: 15 vertices, 25 edges, and 12 faces.

Examples

			2.232950509415690049500415383249682772934080730579181647457441260...
		

Crossrefs

Programs

  • Mathematica
    RealDigits[N[Sqrt[11+4*Sqrt[5]]/2,200]]

Formula

Digits of sqrt(11+4*sqrt(5))/2.

A377751 Decimal expansion of the volume of a truncated icosahedron with unit edge length.

Original entry on oeis.org

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

Views

Author

Paolo Xausa, Nov 07 2024

Keywords

Examples

			55.28773075812273923639861693886121953098664736582...
		

Crossrefs

Cf. A377750 (surface area), A377752 (circumradius), A205769 (midradius + 1), A377787 (Dehn invariant).
Cf. A102208 (analogous for a regular icosahedron).
Cf. A002163.

Programs

  • Mathematica
    First[RealDigits[(125 + 43*Sqrt[5])/4, 10, 100]] (* or *)
    First[RealDigits[PolyhedronData["TruncatedIcosahedron", "Volume"], 10, 100]]
  • PARI
    (125 + 43*sqrt(5))/4 \\ Charles R Greathouse IV, Feb 05 2025

Formula

Equals (125 + 43*sqrt(5))/4 = (125 + 43*A002163)/4.

A386000 Decimal expansion of the volume of a tridiminished icosahedron with unit edge.

Original entry on oeis.org

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

Views

Author

Paolo Xausa, Jul 14 2025

Keywords

Comments

The tridiminished icosahedron is Johnson solid J_63.

Examples

			1.277186493437438661452675653379955568670180...
		

Crossrefs

Cf. A386001 (surfacea area).

Programs

  • Mathematica
    First[RealDigits[5/8 + 7*Sqrt[5]/24, 10, 100]] (* or *)
    First[RealDigits[PolyhedronData["J63", "Volume"], 10, 100]]

Formula

Equals 5/8 + 7*sqrt(5)/24 = 5/8 + 7*A002163/24.
Equals A102208 - 3*A179552 = A386002 - A020829.
Equals the largest root of 144*x^2 - 180*x - 5.
Previous Showing 21-30 of 37 results. Next