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.

A378354 Decimal expansion of the dihedral angle, in radians, between any two adjacent faces in a (small) triakis octahedron.

Original entry on oeis.org

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

Views

Author

Paolo Xausa, Nov 24 2024

Keywords

Comments

The (small) triakis octahedron is the dual polyhedron of the truncated cube.

Examples

			2.57174440034566846791285405092806379355115694111...
		

Crossrefs

Cf. A378351 (surface area), A378352 (volume), A378353 (inradius), A201488 (midradius).
Cf. A019669 and A195698 (dihedral angles of a truncated cube).
Cf. A377342.

Programs

  • Mathematica
    First[RealDigits[ArcCos[-(3 + 8*Sqrt[2])/17], 10, 100]] (* or *)
    First[RealDigits[First[PolyhedronData["TriakisOctahedron", "DihedralAngles"]], 10, 100]]

Formula

Equals arccos(-(3 + 8*sqrt(2))/17) = arccos(-(3 + A377342)/17).

A377341 Decimal expansion of the surface area of a truncated octahedron with unit edge length.

Original entry on oeis.org

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

Views

Author

Paolo Xausa, Oct 25 2024

Keywords

Examples

			26.78460969082652752232935609807046840331366304572...
		

Crossrefs

Cf. A377342 (volume), A020797 (circumradius/10), A152623 (midradius).
Cf. A010469 (analogous for a regular octahedron).
Cf. A002194.

Programs

  • Mathematica
    First[RealDigits[6 + 12*Sqrt[3], 10, 100]] (* or *)
    First[RealDigits[PolyhedronData["TruncatedOctahedron", "SurfaceArea"], 10, 100]]

Formula

Equals 6 + 12*sqrt(3) = 6 + 12*A002194.

A386461 Decimal expansion of the surface area of a biaugmented truncated cube with unit edges.

Original entry on oeis.org

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

Views

Author

Paolo Xausa, Jul 23 2025

Keywords

Comments

The biaugmented truncated cube is Johnson solid J_67.

Examples

			36.241911729260269564523295159701074096328596018257...
		

Crossrefs

Cf. A010524 (volume - 9).

Programs

  • Mathematica
    First[RealDigits[18 + 8*Sqrt[2] + Sqrt[48], 10, 100]] (* or *)
    First[RealDigits[PolyhedronData["J67", "SurfaceArea"], 10, 100]]

Formula

Equals 2*(9 + 4*sqrt(2) + 2*sqrt(3)) = 2*(9 + A010487 + A010469) = 18 + A377342 + A010502.
Equals the largest root of x^4 - 72*x^3 + 1592*x^2 - 10656*x - 2672.

A381687 Decimal expansion of the isoperimetric quotient of a truncated octahedron.

Original entry on oeis.org

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

			0.753366625166156882229489414578751361927704595866...
		

Crossrefs

Cf. A377341 (surface area), A377342 (volume).

Programs

  • Mathematica
    First[RealDigits[64*Pi/(3*(1 + 2*Sqrt[3])^3), 10, 100]]

Formula

Equals 36*Pi*A377342^2/(A377341^3).
Equals 64*Pi/(3*(1 + 2*sqrt(3))^3) = 64*A000796/(3*(1 + A010469)^3).

A379214 Decimal expansion of (sqrt(3) + sqrt(5) + 2*sqrt(6))/(8*sqrt(2)).

Original entry on oeis.org

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

Views

Author

Stefano Spezia, Dec 23 2024

Keywords

Examples

			0.78374816457669166276912268657263121209104522720146...
		

References

  • Steven R. Finch, Mathematical Constants, Encyclopedia of Mathematics and its Applications, vol. 94, Cambridge University Press, 2003, Section 8.6, p. 505.

Crossrefs

Programs

  • Mathematica
    RealDigits[(Sqrt[3]+Sqrt[5]+2Sqrt[6])/(8Sqrt[2]),10,100][[1]]

Formula

Minimal polynomial: 16777216*x^8 - 16777216*x^6 + 4595712*x^4 - 385024*x^2 + 2401. - Stefano Spezia, Aug 03 2025
Showing 1-5 of 5 results.