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 1-5 of 5 results.

A381671 Decimal expansion of the isoperimetric quotient of a regular tetrahedron.

Original entry on oeis.org

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

Views

Author

Paolo Xausa, Mar 03 2025

Keywords

Comments

Polya (1954) defines the isoperimetric quotient of a solid as 36*Pi*V^2/(S^3), where V and S are the volume and surface area of the solid, respectively.
The isoperimetric quotient of a sphere is 1.

Examples

			0.30229989403903630843234637627369262204734437468212...
		

References

  • George Polya, Mathematics and Plausible Reasoning, Vol. 1: Induction and Analogy in Mathematics, Princeton University Press, Princeton, New Jersey, 1954. See pp. 188-189, exercise 43.

Crossrefs

Cf. A273633 (sphericity).
Cf. isoperimetric quotient of other Platonic solids: A019673 (cube), A073010 (octahedron), A374772 (dodecahedron), A381672 (icosahedron).

Programs

  • Mathematica
    First[RealDigits[Pi/(6*Sqrt[3]), 10, 100]]

Formula

Equals Pi/(6*sqrt(3)) = A019673/A002194.

A273637 Decimal expansion of ((Pi*(3+sqrt(5))^2)/(60*sqrt(3)))^(1/3), the sphericity of the icosahedron.

Original entry on oeis.org

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

Views

Author

Felix Fröhlich, May 27 2016

Keywords

Examples

			0.93932565156763615941610143241466136614288864170479161093295918...
		

Crossrefs

Programs

  • Mathematica
    RealDigits[Surd[(Pi (3+Sqrt[5])^2)/(60Sqrt[3]),3],10,120][[1]] (* Harvey P. Dale, Nov 16 2022 *)
  • PARI
    default(realprecision, 50080); my(x=((Pi*(3+sqrt(5))^2)/(60*sqrt(3)))^(1/3)); for(k=1, 100, my(d=floor(x)); x=(x-d)*10; print1(d, ", "))

A273634 Decimal expansion of (Pi/6)^(1/3), the sphericity of the cube.

Original entry on oeis.org

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

Views

Author

Felix Fröhlich, May 27 2016

Keywords

Examples

			0.80599597700823482035848342331964246947230703616193077784614603...
		

Crossrefs

Programs

  • Mathematica
    RealDigits[Surd[Pi/6, 3], 10, 120][[1]] (* Amiram Eldar, Jun 29 2023 *)
  • PARI
    default(realprecision, 50080); my(x=(Pi/6)^(1/3)); for(k=1, 100, my(d=floor(x)); x=(x-d)*10; print1(d, ", "))

Formula

Equals cube root of A019673. - Michel Marcus, May 27 2016

A273635 Decimal expansion of (Pi/(3*sqrt(3)))^(1/3), the sphericity of the octahedron.

Original entry on oeis.org

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

Views

Author

Felix Fröhlich, May 27 2016

Keywords

Examples

			0.84558252053658756632718815977306625250200668234085959800699611...
		

Crossrefs

Programs

  • Mathematica
    RealDigits[Surd[Pi/(3Sqrt[3]),3],10,120][[1]] (* Harvey P. Dale, Jan 07 2023 *)
  • PARI
    default(realprecision, 50080); my(x=(Pi/(3*sqrt(3)))^(1/3)); for(k=1, 100, my(d=floor(x)); x=(x-d)*10; print1(d, ", "))

Formula

Equals cube root of A093602. - Michel Marcus, May 27 2016

Extensions

Definition corrected by Georg Fischer, Jul 12 2021

A273636 Decimal expansion of ((Pi*(15+7*sqrt(5))^2)/(12*(25+10*sqrt(5))^(3/2)))^(1/3), the sphericity of the dodecahedron.

Original entry on oeis.org

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

Views

Author

Felix Fröhlich, May 27 2016

Keywords

Examples

			0.91045318140924227916953803446625862857458658029433801265061554...
		

Crossrefs

Programs

  • Mathematica
    RealDigits[((Pi*(15 + 7*Sqrt[5])^2)/(12*(25 + 10*Sqrt[5])^(3/2)))^(1/3), 10, 120][[1]] (* Amiram Eldar, Jun 29 2023 *)
  • PARI
    default(realprecision, 50080); my(x=((Pi*(15+7*sqrt(5))^2)/(12*(25+10*sqrt(5))^(3/2)))^(1/3)); for(k=1, 100, my(d=floor(x)); x=(x-d)*10; print1(d, ", "))
Showing 1-5 of 5 results.