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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A223537 Compressed nim-multiplication table read by antidiagonals.

Original entry on oeis.org

1, 2, 2, 4, 3, 8, 8, 8, 12, 12, 16, 12, 5, 4, 192, 32, 32, 10, 10, 64, 64, 64, 48, 128, 15, 160, 128, 240, 128, 128, 192, 192, 240, 240, 80, 80, 256, 192, 80, 64, 17, 80, 96, 160, 20480, 512, 512, 160, 160, 34, 34, 176, 176, 40960, 40960, 1024
Offset: 0

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Author

Tilman Piesk, Mar 21 2013

Keywords

Comments

A nim-multiplication table (A051775) of size 2^2^n can be compressed to a matrix of size 2^n, using Walsh permutations. As the nim-multiplication tables are submatrices to the bigger ones, also the compressions are submatrices to the bigger ones, leading to this infinite array.
This array is closely related to the nim-multiplication table powers of 2 (A223541). Both arrays can be seen as different views of the same cubic binary tensor.
The diagonal is A001317 (Sierpinski triangle rows read like binary numbers).
The elements of this array are listed in A223539. In the key-matrix A223538 the entries of this array (which become very large) are replaced by the corresponding index numbers of A223539. (Surprisingly, the key-matrix seems to be interesting on its own.)

Crossrefs

Formula

a(m,n) = A223539( A223538(m,n) ).
a(n,n) = A001317(n).
a(1,n) = A134683(n+1).

A223539 List of entries in the compressed nim-multiplication table (A223537).

Original entry on oeis.org

1, 2, 3, 4, 5, 8, 10, 12, 15, 16, 17, 32, 34, 48, 51, 64, 68, 80, 85, 96, 128, 136, 160, 170, 176, 192, 204, 208, 240, 255, 256, 257, 512, 514, 768, 771, 1024, 1028, 1280, 1285, 2048, 2056, 2560, 2570, 3072, 3084, 3840, 3855, 4096, 4112, 4352
Offset: 1

Views

Author

Tilman Piesk, Mar 21 2013

Keywords

Comments

List of entries in the compressed nim-multiplication table (A223537).
The first 1, 3, 9, 30, 108, 402, 1548, 6072, 24048, ... entries are the distinct entries of A223537-submatrices of size 1, 2, 4, 8, 16, 32, 64, 128, 256, ... (A000079).

Examples

			Biggest entry of 8 X 8 submatrix of A223537 is A223537(7,7) = a(29) = 255.
Biggest entry of 16 X 16 submatrix of A223537 is A223537(15,15) = a(107) = 65535.
		

Crossrefs

Formula

A223537(m,n) = a(A223538(m,n)).
Showing 1-2 of 2 results.