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 1-4 of 4 results.

A068599 Number of n-uniform tilings.

Original entry on oeis.org

11, 20, 61, 151, 332, 673, 1472, 2850, 5960, 11866, 24459, 49794, 103082
Offset: 1

Views

Author

Brian Galebach, Mar 28 2002

Keywords

Comments

Sequence gives the number of edge-to-edge regular-polygon tilings having n vertex classes relative to the symmetry of the tiling. Allows tilings with two or more vertex classes having the same arrangement of surrounding polygons (vertex type), as long as those classes are distinct within the symmetry of the tiling .
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.

References

  • Marek Čtrnáct, Postings to Tiling Mailing List, 2021 (a(13) announced in posting on Dec 21 2021).
  • B. Grünbaum and G. C. Shephard, Tilings and Patterns, an Introduction, Freeman, 1989; Exercise *6 on p. 70. See Sections 2.1 and 2.2.

Crossrefs

Cf. A068600.

Extensions

151 and 332 found by Brian Galebach on Apr 30 2002, 673 on Aug 06 2003, 1472 on Apr 28 2020
a(8)-a(13) found by Marek Čtrnáct in 2021. - N. J. A. Sloane, Dec 21 2021

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.
Showing 1-4 of 4 results.