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 1-10 of 36 results. Next

A098427 Order of symmetry group of the five Platonic solids sorted on the number of faces (A053016).

Original entry on oeis.org

24, 48, 48, 120, 120
Offset: 1

Views

Author

Lekraj Beedassy, Oct 26 2004

Keywords

Comments

Orders of the groups S_4, S_4 X C_2, S_4 X C_2, A_5 X C_2, A_5 X C_2.

A136254 Generator for the finite sequence A053016.

Original entry on oeis.org

4, 6, 8, 12, 20, 34, 56, 88, 132, 190, 264, 356, 468, 602, 760, 944, 1156, 1398, 1672, 1980, 2324, 2706, 3128, 3592, 4100, 4654, 5256, 5908, 6612, 7370, 8184, 9056, 9988, 10982, 12040, 13164, 14356
Offset: 0

Views

Author

Rolf Pleisch, Mar 17 2008

Keywords

Crossrefs

Cf. A053016.

Programs

  • Mathematica
    CoefficientList[Series[(8*x^2 - 10*x + 4)/(x^4 - 4*x^3 + 6*x^2 - 4*x + 1), {x, 0, 50}], x] (* G. C. Greubel, Feb 23 2017 *)
    LinearRecurrence[{4,-6,4,-1},{4,6,8,12},40] (* Harvey P. Dale, Jul 23 2018 *)
  • PARI
    x='x+O('x^50); Vec((8*x^2 - 10*x + 4)/(x^4 - 4*x^3 + 6*x^2 - 4*x + 1)) \\ G. C. Greubel, Feb 23 2017

Formula

a(n) = n^3/3 - n^2 + 8n/3 + 4.
G.f.: (8*x^2 - 10*x + 4)/(x^4 - 4*x^3 + 6*x^2 - 4*x + 1). - Alexander R. Povolotsky, Mar 31 2008
From G. C. Greubel, Feb 23 2017: (Start)
E.g.f.: (1/3)*(12 + 6*x + x^3)*exp(x).
a(n) = 4*a(n-1) - 6*a(n-2) + 4*a(n-3) - a(n-4). (End)

A078785 Duplicate of A053016.

Original entry on oeis.org

4, 6, 8, 12, 20
Offset: 0

Views

Author

Keywords

A063723 Number of vertices in the Platonic solids (in the order tetrahedron, cube, octahedron, dodecahedron, icosahedron).

Original entry on oeis.org

4, 8, 6, 20, 12
Offset: 1

Views

Author

Henry Bottomley, Aug 14 2001

Keywords

Comments

The preferred order for these five numbers is 4, 6, 8, 12, 20 (tetrahedron, octahedron, cube, icosahedron, dodecahedron), as in A053016. - N. J. A. Sloane, Nov 05 2020
Also number of faces of Platonic solids ordered by increasing ratios of volumes to their respective circumscribed spheres. See cross-references for actual ratios. - Rick L. Shepherd, Oct 04 2009
Also the expected lengths of nontrivial random walks along the edges of a Platonic solid from one vertex back to itself. - Jens Voß, Jan 02 2014

Examples

			a(2) = 8 since a cube has eight vertices.
		

Crossrefs

Cf. A165922 (tetrahedron), A049541 (octahedron), A165952 (cube), A165954 (icosahedron), A165953 (dodecahedron). - Rick L. Shepherd, Oct 04 2009
Cf. A234974. - Jens Voß, Jan 02 2014

Formula

a(n) = A063722(n) - A053016(n) + 2.

A338622 Irregular table read by rows: The number of k-faced polyhedra, where k>=4, formed when the five Platonic solids, in the order tetrahedron, octahedron, cube, icosahedron, dodecahedron, are internally cut by all the planes defined by any three of their vertices.

Original entry on oeis.org

1, 8, 72, 24, 2160, 360, 205320, 208680, 94800, 34200, 7920, 1560, 120
Offset: 1

Views

Author

Scott R. Shannon, Nov 04 2020

Keywords

Comments

See A338571 for further details and images of this sequence.
The author thanks Zach J. Shannon for producing the images for this sequence.

Examples

			The cube is cut with 14 internal planes defined by all 3-vertex combinations of its 8 vertices. This leads to the creation of 72 4-faced polyhedra and 24 5-faced polyhedra, 96 pieces in all. See A338571 and A333539.
The table is:
1;
8;
72, 24;
2160, 360;
205320, 208680, 94800, 34200, 7920, 1560, 120;
		

Crossrefs

Cf. A338571 (total number of polyhedra), A333539 (n-dimensional cube), A053016, A063722, A063723, A098427, A333543.

Formula

Sum of row n = A338571(n).

A063722 Number of edges in the Platonic solids (in the order tetrahedron, cube, octahedron, dodecahedron, icosahedron).

Original entry on oeis.org

6, 12, 12, 30, 30
Offset: 1

Views

Author

Henry Bottomley, Aug 14 2001

Keywords

Examples

			a(2) = 12 since a cube has twelve edges.
		

Crossrefs

Formula

a(n) = A053016(n)+A063723(n)-2.

A060296 Number of regular convex polytopes in n-dimensional space, or -1 if the number is infinite.

Original entry on oeis.org

1, 1, -1, 5, 6, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3, 3
Offset: 0

Views

Author

Ahmed Fares (ahmedfares(AT)my-deja.com), Mar 24 2001

Keywords

Examples

			a(2) = -1 because of the regular polygons in the plane.
a(3) = 5 because in R^3 the regular convex polytopes are the 5 Platonic solids.
		

References

  • H. S. M. Coxeter, Regular Polytopes, 3rd ed., Dover, NY, 1973.
  • B. Grünbaum, Convex Polytopes. Wiley, NY, 1967, p. 424.
  • P. McMullen and E. Schulte, Abstract Regular Polytopes, Encyclopedia of Mathematics and its Applications, Vol. 92, Cambridge University Press, Cambridge, 2002.

Crossrefs

Programs

  • Mathematica
    PadRight[{1, 1, -1, 5, 6}, 100, 3] (* Paolo Xausa, Jan 29 2025 *)

Formula

a(n) = 3 for all n > 4. - Christian Schroeder, Nov 16 2015

A063924 Number of 3-dimensional cells in the regular 4-dimensional polytopes.

Original entry on oeis.org

5, 8, 16, 24, 120, 600
Offset: 1

Views

Author

Henry Bottomley, Aug 15 2001

Keywords

Comments

Sorted by number of 3-dimensional cells.
Also, number of vertices of the regular 4-dimensional polyhedra. - Douglas Boffey, Aug 12 2012

Examples

			a(2) = 8 since a 4D hypercube contains eight cubes.
		

References

  • H. S. M. Coxeter, Regular Polytopes, 3rd ed., Dover, NY, 1973.

Crossrefs

Formula

a(n) = A063925(n) - A063926(n) + A063927(n).

Extensions

Corrected faces to cells by Douglas Boffey, Aug 12 2012

A063927 Number of vertices in the regular 4-dimensional polytopes.

Original entry on oeis.org

5, 16, 8, 24, 600, 120
Offset: 1

Views

Author

Henry Bottomley, Aug 15 2001

Keywords

Comments

Sorted by number of 3-dimensional faces.

Examples

			a(2) = 16 since a 4D hypercube contains sixteen vertices.
		

References

  • H. S. M. Coxeter, Regular Polytopes, 3rd ed., Dover, NY, 1973.

Crossrefs

Formula

a(n) = A063926(n) - A063925(n) + A063924(n).

A338571 Number of polyhedra formed when the five Platonic solids, in the order tetrahedron, octahedron, cube, icosahedron, dodecahedron, are internally cut by all the planes defined by any three of their vertices.

Original entry on oeis.org

1, 8, 96, 2520, 552600
Offset: 1

Views

Author

Scott R. Shannon, Nov 03 2020

Keywords

Comments

For a Platonic solid create all possible planes defined by connecting any three of its vertices. For example, in the case of a cube this results in fourteen planes; six planes between the pairs of parallel edges connected to each end of the face diagonals, and eight planes from connecting the three vertices adjacent to each corner vertex. Use all the resulting planes to cut the solid into individual smaller polyhedra. The sequence lists the numbers of resulting polyhedra for the Platonic solids, ordered by number of vertices: tetrahedron, octahedron, cube, icosahedron, dodecahedron.
See A338622 for the number and images of the k-faced polyhedra in each dissection for each of the five solids.
The author thanks Zach J. Shannon for producing the images for this sequence.

Examples

			a(1) = 1. The tetrahedron has no internal cutting planes so the single polyhedron after cutting is the tetrahedron itself.
a(2) = 8. The octahedron has 3 internal cutting planes resulting in 8 polyhedra.
a(3) = 96. The cube has 14 internal cutting planes resulting in 96 polyhedra. See also A333539.
a(4) = 2520. The icosahedron has 47 cutting planes resulting in 2520 polyhedra.
See A338622 for a breakdown of the above totals into the corresponding number of k-faced polyhedra.
a(5) = 552600. The dodecahedron has 307 internal cutting planes resulting in 552600 polyhedra. It is the only Platonic solid which produces polyhedra with 6 or more faces.
		

Crossrefs

Cf. A338622 (number of k-faced polyhedra in each dissection), A333539 (n-dimensional cube), A053016, A063722, A063723, A098427.
Showing 1-10 of 36 results. Next