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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.

A375356 T(m, n) is the number of m X n toroidal knot/link mosaics read by rows, with 1 <= n <= m.

Original entry on oeis.org

7, 18, 110, 49, 954, 35237, 171, 11591, 1662837, 308435024, 637, 155310, 86538181, 63440607699, 52006454275147
Offset: 1

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Author

Luc Ta, Aug 20 2024

Keywords

Comments

An m X n mosaic is an m X n array of the 11 tiles given by Lomonaco and Kauffman. A period m X n mosaic is an m X n mosaic whose opposite edges are identified. A toroidal m X n mosaic is an equivalence class of period m X n mosaics up to finite sequences of cyclic rotations of rows and columns. A toroidal mosaic depicts the projection of a knot or link on the surface of a torus iff the connection points of each tile coincide with those of the contiguous tiles and with those of the tiles on identified edges.
The first five rows of the triangle are from Table 2 of Oh, Hong, Lee, Lee, and Yeon.
Clearly, T(m,n) <= A375355(m,n) for all m,n, with equality iff m = n = 1.

Examples

			Triangle begins:
    7;
   18,    110;
   49,    954,    35237;
  171,  11591,  1662837,   308435024;
  637, 155310, 86538181, 63440607699, 52006454275147;
  ...
The only period 1 X 1 link mosaics are given by the tiles T_0 and T_5 through T_10 of Lomonaco and Kauffman. None of these mosaics are cyclic rotations of rows and columns of the others (since there are no rows or columns to permute in the first place). Therefore, T(1,1) = 7.
An exhaustive list of all 110 distinct 2 X 2 toroidal link mosaics is given collectively by Appendix A of Carlisle and Laufer and Figure 4 of Oh, Hong, Lee, Lee, and Yeon.
		

Crossrefs

The main diagonal T(n,n) contains A375357 as a subsequence.