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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A359000 Number of undirected n-cycles of the octahedral graph.

Original entry on oeis.org

8, 15, 24, 16
Offset: 3

Views

Author

Seiichi Manyama, Dec 10 2022

Keywords

Comments

a(3) = 8 = A053016(3).
a(6) = 16 = A268283(3)/2.

Crossrefs

A359001 Number of undirected n-cycles of the dodecahedral graph.

Original entry on oeis.org

12, 0, 0, 30, 20, 36, 120, 100, 60, 180, 180, 90, 180, 130, 0, 30
Offset: 5

Views

Author

Seiichi Manyama, Dec 10 2022

Keywords

Comments

a(5) = 12 = A053016(4).
a(20) = 30 = A268283(4)/2.

Crossrefs

A359002 Number of undirected n-cycles of the icosahedral graph.

Original entry on oeis.org

20, 30, 72, 240, 720, 1620, 2680, 3336, 2880, 1280
Offset: 3

Views

Author

Seiichi Manyama, Dec 10 2022

Keywords

Comments

a(3) = 20 = A053016(5).
a(12) = 1280 = A268283(5)/2.

Crossrefs

A201187 Number of distinct planar nets of the Platonic solids (in the order tetrahedron, cube, octahedron, dodecahedron, icosahedron).

Original entry on oeis.org

2, 11, 11, 43380, 43380
Offset: 1

Views

Author

Andrew McFarland, Nov 28 2011

Keywords

Comments

A Platonic solid and its dual have the same number of nets.

Examples

			a(1) = 2 since a tetrahedron has 2 distinct nets.
		

Crossrefs

Cf. A053016.

A299028 Number of vertices in the iterated clique graphs of the 1-skeleton of Plato's icosahedron.

Original entry on oeis.org

12, 20, 32, 92, 472
Offset: 0

Views

Author

José Hernández, Feb 01 2018

Keywords

Comments

It is known that the sequence of orders of the iterated clique graphs of the icosahedron goes to infinity.

Examples

			By definition, the zeroth iterated clique graph of a graph G is equal to G itself; since the icosahedron has 12 vertices, a(0)=12.
The first iterated clique graph of the icosahedron has 20 vertices; hence, a(1)=20.
		

Crossrefs

Programs

  • YAGS
    K:=CliqueGraph;; g:=Icosahedron;; kg:=K(g);; Order(kg);
    # It outputs the number of vertices in the first iterated
    # clique graph of the icosahedron.

A299030 Number of vertices in the iterated clique graphs of the 1-skeleton of Plato's octahedron.

Original entry on oeis.org

6, 8, 16, 256, 340282366920938463463374607431768211456
Offset: 0

Views

Author

José Hernández, Feb 01 2018

Keywords

Comments

The octahedron was the first known example of a k-divergent graph.

Examples

			By definition, the zeroth iterated clique graph of a graph G is equal to G itself; since the octahedron has 6 vertices, a(0)=6.
The first iterated clique graph of the octahedron has 8 vertices; hence, a(1)=8.
		

Crossrefs

Programs

  • Mathematica
    Nest[Sqrt[2]^#&, 6, n] (* Omar Antolín-Camarena, May 16 2022 *)
  • YAGS
    K:=CliqueGraph;; g:=Octahedron;; kg:=K(g);; Order(kg);
    # It outputs the number of vertices in the first iterated
    # clique graph of the octahedron.

Formula

a(n) = sqrt(2)^sqrt(2)^...^sqrt(2)^6 with n occurrences of sqrt(2). - Omar Antolín-Camarena, May 16 2022

Extensions

a(4) from Omar Antolín-Camarena, May 16 2022

A359202 Number of (bidimensional) faces of regular m-polytopes for m >= 3.

Original entry on oeis.org

4, 6, 8, 10, 12, 20, 24, 32, 35, 56, 80, 84, 96, 120, 160, 165, 220, 240, 280, 286, 364, 448, 455, 560, 672, 680, 720, 816, 960, 969, 1140, 1200, 1320, 1330, 1540, 1760, 1771, 1792, 2024, 2288, 2300, 2600, 2912, 2925, 3276, 3640, 3654, 4060, 4480, 4495, 4608
Offset: 1

Views

Author

Marco Ripà, Dec 20 2022

Keywords

Comments

In 3 dimensions there are five (convex) regular polytopes and they have 4, 6, 8, 12, or 20 (bidimensional) faces (A053016).
In 4 dimensions there are six regular 4-polytopes and they have 10, 24, 32, 96, 720, or 1200 faces (A063925).
In m >= 5 dimensions, there are only 3 regular polytopes (i.e., the m-simplex, the m-cube, and the m-crosspolytope) so that we can sort their number of bidimensional faces in ascending order and define the present sequence.

Examples

			6 is a term since a cube has 6 faces.
		

Crossrefs

Cf. A359201 (edges), A359662 (cells).

Formula

{a(n), n >= 1} = {{12, 96, 720, 1200} U {A000292} U {A001788} U {A130809}} \ {0, 1}.

A062554 Products of numbers of faces of Platonic solids, i.e., of {4,6,8,12,20}.

Original entry on oeis.org

4, 6, 8, 12, 16, 20, 24, 32, 36, 48, 64, 72, 80, 96, 120, 128, 144, 160, 192, 216, 240, 256, 288, 320, 384, 400, 432, 480, 512, 576, 640, 720, 768, 864, 960, 1024, 1152, 1280, 1296, 1440, 1536, 1600, 1728, 1920, 2048, 2304, 2400, 2560, 2592, 2880, 3072, 3200
Offset: 1

Views

Author

Neil Fernandez, Jul 02 2001

Keywords

Crossrefs

Programs

  • PARI
    ismult(n, v, vp) = {for (k=1, #v, q = n/v[k]; if ((type(q)== "t_INT") && vecsearch(vp, q), return (1)););}
    lista(nn) = {v = [4,6,8,12,20]; vp = []; for (n=2, nn, if (vecsearch(v, n) || ismult(n, v, vp), print1(n, ", "); vp = concat(vp, n);););} \\ Michel Marcus, Feb 03 2015

Extensions

More terms from Michel Marcus, Feb 03 2015

A140800 Total number of vertices in all finite n-dimensional convex regular polytopes, or 0 if the number is infinite.

Original entry on oeis.org

1, 2, 0, 50, 773, 48, 83, 150, 281, 540, 1055, 2082, 4133, 8232, 16427, 32814, 65585, 131124, 262199, 524346, 1048637, 2097216, 4194371, 8388678, 16777289, 33554508, 67108943, 134217810, 268435541, 536871000, 1073741915, 2147483742
Offset: 0

Views

Author

Jonathan Vos Post, Jul 15 2008

Keywords

Comments

Andrew Weimholt suggests a related sequence, namely "total number of vertices in all finite n-dimensional regular polytopes, or 0 if the number is infinite, includes both convex and non-convex, beginning: 1, 2, 0, 106, 2453, 48, 83, 150, 281, 540, ... and writes that the sequence of just the non-convex cases (0, 0, -1, 56, 1680, 0, 0, 0, ..., where "-1" indicates infinity as zero is otherwise employed) is not as interesting, since it's all zeros from a(5) on.

Examples

			a(0) = 1 because the 0-D regular polytope is the point.
a(1) = 2 because the only regular 1-D polytope is the line segment, with 2 vertices, one at each end.
a(2) = 0, indicating infinity, because the regular k-gon has k vertices.
a(3) = 50 (4 for the tetrahedron, 6 for the octahedron, 8 for the cube, 12 for the icosahedron, 20 for the dodecahedron) = the sum of A053016.
a(4) = 773 = 5 + 8 + 16 + 24 + 120 + 600 = sum of A063924.
For n>4 there are only the three regular n-dimensional polytopes, the simplex with n+1 vertices, the hypercube with 2^n vertices and the hyperoctahedron = cross polytope = orthoplex with 2*n vertices, for a total of A086653(n) + 1 = 2^n + 3*n + 1 (again restricted to n > 4).
		

References

  • H. S. M. Coxeter, Regular Polytopes, 3rd ed., Dover, NY, 1973.
  • Branko Grunbaum, Convex Polytopes, second edition (first edition (1967) written with the cooperation of V. L. Klee, M. Perles and G. C. Shephard; second edition (2003) prepared by V. Kaibel, V. L. Klee and G. M. Ziegler), Graduate Texts in Mathematics, Vol. 221, Springer 2003.
  • P. McMullen and E. Schulte, Abstract Regular Polytopes, Encyclopedia of Mathematics and its Applications, Vol. 92, Cambridge University Press, Cambridge, 2002.

Crossrefs

Programs

  • Mathematica
    LinearRecurrence[{4, -5, 2}, {1, 2, 0, 50, 773, 48, 83, 150}, 32] (* Georg Fischer, May 03 2019 *)

Formula

For n > 4, a(n) = A086653(n) + 1 = 2^n + 3*n + 1.
G.f.: -(1488*x^7 - 3656*x^6 + 2794*x^5 - 569*x^4 - 58*x^3 + 3*x^2 + 2*x - 1)/((1-x)^2*(1-2*x)). [Colin Barker, Sep 05 2012]

Extensions

a(14)-a(15) corrected by Georg Fischer, May 02 2019

A146528 a(0) = 4; for n >= 1, a(n) = 2^n + 4.

Original entry on oeis.org

4, 6, 8, 12, 20, 36, 68, 132, 260, 516, 1028, 2052, 4100, 8196, 16388, 32772, 65540, 131076, 262148, 524292, 1048580, 2097156, 4194308, 8388612, 16777220, 33554436, 67108868, 134217732, 268435460, 536870916, 1073741828
Offset: 0

Views

Author

Roger L. Bagula, Oct 30 2008

Keywords

Comments

This is one of many possible ways to extend the Platonic solids sequence A053016.

Crossrefs

Essentially the same as A140504.

Programs

  • Mathematica
    v[n_] := 2*(If[n == 0, 0, 2^(n - 1)] + 2); Table[v[n], {n, 0, 30}]

Formula

a(n)=A140504(n), n>0. [From R. J. Mathar, Nov 05 2008]

Extensions

Edited by N. J. A. Sloane, Mar 21 2021
Previous Showing 21-30 of 36 results. Next