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 1-6 of 6 results.

A068600 Number of n-uniform tilings having n different arrangements of polygons about their vertices.

Original entry on oeis.org

11, 20, 39, 33, 15, 10, 7, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0
Offset: 1

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Author

Brian Galebach, Mar 28 2002

Keywords

Comments

Sequence gives the number of edge-to-edge regular-polygon tilings having n topologically distinct vertex types, with each vertex type having a different arrangement of surrounding polygons. Does not allow for tilings with two or more vertex types having the same arrangement of surrounding polygons, even when those vertices are topologically distinct. There are no 8- or higher-uniform tilings having the equivalent number of distinct polygon arrangements.
There are eleven 1-uniform tilings (also called the "Archimedean" tessellations) which comprise the three regular tessellations (all triangles, squares, or hexagons) plus the eight semiregular tessellations. (See A250120. - N. J. A. Sloane, Nov 29 2014)

References

  • This sequence was originally calculated by Otto Krotenheerdt.
  • Branko Grünbaum and G. C. Shephard, Tilings and Patterns. W. H. Freeman, New York, 1987, page 69.
  • Krotenheerdt, Otto. "Die homogenen Mosaike n-ter Ordnung in der euklidischen Ebene," Wiss. Z. Martin-Luther-Univ. Halle-Wittenberg. Math.-natur. Reihe, 18(1969), 273-290; 19 (1970)19-38 and 97-122.

Crossrefs

Cf. A068599.
List of coordination sequences for uniform planar nets: A008458 (the planar net 3.3.3.3.3.3), A008486 (6^3), A008574 (4.4.4.4 and 3.4.6.4), A008576 (4.8.8), A008579 (3.6.3.6), A008706 (3.3.3.4.4), A072154 (4.6.12), A219529 (3.3.4.3.4), A250120(3.3.3.3.6), A250122 (3.12.12).

A268184 Number of n-isohedral edge-to-edge tilings of regular polygons.

Original entry on oeis.org

3, 13, 29, 70, 140, 267, 559
Offset: 1

Views

Author

Brian Galebach, Jan 28 2016

Keywords

Comments

An n-isohedral tiling has n transitivity classes (or "orbits") of faces with respect to the symmetry group of the tiling.

Examples

			The three 1-isohedral tilings are the regular tilings (triangles, squares, hexagons). Of the 13 2-isohedral tilings, there are three with triangles and squares, eight with triangles and hexagons, one with triangles and dodecagons, and one with squares and octagons.
		

Crossrefs

Analogous to the n-uniform edge-to-edge tilings, which has n orbits of vertices, as opposed to faces (A068599).

Extensions

a(7) from Brian Galebach, Dec 23 2016

A299780 Triangle read by rows: T(n,m) = number of n-uniform tilings having m different arrangements of polygons about their vertices, n >= 1 and 1 <= m <= n.

Original entry on oeis.org

11, 0, 20, 0, 22, 39, 0, 33, 85, 33, 0, 74, 149, 94, 15, 0, 100, 284, 187, 92, 10, 0
Offset: 1

Views

Author

Omar E. Pol, Mar 30 2018

Keywords

Comments

Taken from Brian Galebach's square array (see link).

Examples

			Triangle begins:
  11;
   0,  20;
   0,  22,  39;
   0,  33,  85,  33;
   0,  74, 149,  94, 15;
   0, 100, 284, 187, 92, 10;
...
Other known positive terms are T(7,7) = 7, T(8,7) = 20, T(9,8) = 8, T(10,8) = 27 and T(11,9) = 1.
		

Crossrefs

Row sums gives A068599.
Leading diagonal is A068600.
Column 1 gives 11 together with A000004.

A299781 Triangle read by rows: T(n,m) = number of k-uniform tilings having m different arrangements of polygons about their vertices, for k = 1..n, with 1 <= m <= n.

Original entry on oeis.org

11, 11, 20, 11, 42, 39, 11, 75, 124, 33, 11, 149, 273, 127, 15, 11, 249, 557, 314, 107, 10, 11
Offset: 1

Views

Author

Omar E. Pol, Mar 30 2018

Keywords

Comments

Column m lists the partial sums of the m-th column of triangle A299780.

Examples

			Triangle begins:
  11;
  11,  20;
  11,  42,  39;
  11,  75, 124,  33;
  11, 149, 273, 127,  15;
  11, 249, 557, 314, 107, 10;
...
		

Crossrefs

Column 1 gives A010850.
Leading diagonal is A068600.
Row sums give A299782.

A299782 a(n) is the total number of k-uniform tilings, for k = 1..n.

Original entry on oeis.org

11, 31, 92, 243, 575, 1248
Offset: 1

Views

Author

Omar E. Pol, Mar 30 2018

Keywords

Examples

			For n = 3 there are 11 uniform tilings, 20 2-uniform tilings and 61 3-uniform tilings. The sum of them is 11 + 20 + 61 = 92, so (3) = 92.
		

Crossrefs

Partial sums of A068599.
Row sums of A299781.

A242941 a(n) is the number of convex uniform tessellations in dimension n.

Original entry on oeis.org

1, 11, 28, 143
Offset: 1

Views

Author

Felix Fröhlich, May 27 2014

Keywords

Comments

Terms for n > 4 have not been determined so far. Alfredo Andreini in 1905 gave a value of 25 for a(3), later found to be incorrect. The value 28 for a(3) was given by Norman Johnson in 1991 and later in 1994 independently by Branko Grünbaum. The value for a(4) was given by George Olshevsky in 2006.
Deza and Shtogrin (2000) agree that the value of a(3) is 28, although the authors do not provide a proof. - Felix Fröhlich, Nov 29 2014
From Felix Fröhlich, Feb 03 2019: (Start)
The 11 convex uniform tilings are all illustrated in Kepler, 1619. For an argument that exactly 11 such tilings exist, see Grünbaum, Shephard, 1977.
In dimension 2, the definition of "uniform polytope" usually seems to be equivalent to the regular polygons in order to exclude polygons that alternate two different edge-lengths. Applying this principle retroactively to dimension 1 (as done, as I assume, by Coxeter, see Coxeter, 1973, p. 129) yields a(1) = 1. (End)

References

  • H. S. M. Coxeter, Regular Polytopes, Third Edition, Dover Publications, 1973, ISBN 9780486614809.
  • B. Grünbaum, Uniform tilings of 3-space, Geombinatorics, Vol. 4, No. 2 (1994), 49-56.
  • N. W. Johnson, Uniform Polytopes, [To appear, cf. Weiss, Stehle, 2017].

Crossrefs

Cf. A068599.
List of coordination sequences for the 11 uniform 2D tilings: A008458(the planar net 3.3.3.3.3.3), A008486 (6^3), A008574 (4.4.4.4 and 3.4.6.4), A008576 (4.8.8), A008579 (3.6.3.6), A008706(3.3.3.4.4), A072154 (4.6.12), A219529 (3.3.4.3.4), A250120(3.3.3.3.6), A250122 (3.12.12).
List of coordination sequences for the 28 uniform 3D tilings: cab: A299266, A299267; crs: A299268, A299269; fcu: A005901, A005902; fee: A299259, A299265; flu-e: A299272, A299273; fst: A299258, A299264; hal: A299274, A299275; hcp: A007899, A007202; hex: A005897, A005898; kag: A299256, A299262; lta: A008137, A299276; pcu: A005899, A001845; pcu-i: A299277, A299278; reo: A299279, A299280; reo-e: A299281, A299282; rho: A008137, A299276; sod: A005893, A005894; sve: A299255, A299261; svh: A299283, A299284; svj: A299254, A299260; svk: A010001, A063489; tca: A299285, A299286; tcd: A299287, A299288; tfs: A005899, A001845; tsi: A299289, A299290; ttw: A299257, A299263; ubt: A299291, A299292; bnn: A007899, A007202. See the Proserpio link in A299266 for overview.

Extensions

Edited by N. J. A. Sloane, Feb 15 2018
Edited by Felix Fröhlich, Feb 03-10 2019
Showing 1-6 of 6 results.