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.

A307301 Array read by antidiagonals: Sprague-Grundy values for the game NimHof with rules [1,0], [3,1], [0,1].

Original entry on oeis.org

0, 1, 1, 2, 0, 2, 3, 3, 3, 3, 4, 2, 0, 2, 4, 5, 5, 4, 1, 5, 5, 6, 4, 1, 0, 6, 4, 6, 7, 7, 6, 6, 1, 7, 7, 7, 8, 6, 5, 7, 0, 6, 4, 6, 8, 9, 9, 8, 8, 2, 2, 8, 5, 9, 9, 10, 8, 7, 4, 3, 0, 3, 9, 10, 8, 10, 11, 11, 10, 5, 9, 9, 1, 8, 5, 11, 11, 11, 12, 10, 9, 11
Offset: 0

Views

Author

N. J. A. Sloane, Apr 13 2019

Keywords

Comments

The game NimHof with a list of rules R means that for each rule [a,b] you can move from cell [x,y] to any cell [x-i*a,y-i*b] as long as neither coordinate is negative. See the Friedman et al. article for further details.

Examples

			The initial antidiagonals are:
[0]
[1, 1]
[2, 0, 2]
[3, 3, 3, 3]
[4, 2, 0, 2, 4]
[5, 5, 4, 1, 5, 5]
[6, 4, 1, 0, 6, 4, 6]
[7, 7, 6, 6, 1, 7, 7, 7]
[8, 6, 5, 7, 0, 6, 4, 6, 8]
[9, 9, 8, 8, 2, 2, 8, 5, 9, 9]
[10, 8, 7, 4, 3, 0, 3, 9, 10, 8, 10]
[11, 11, 10, 5, 9, 9, 1, 8, 5, 11, 11, 11]
[12, 10, 9, 11, 10, 1, 0, 3, 7, 7, 8, 10, 12]
...
The triangle begins:
[0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12]
[1, 0, 3, 2, 5, 4, 7, 6, 9, 8, 11, 10]
[2, 3, 0, 1, 6, 7, 4, 5, 10, 11, 8]
[3, 2, 4, 0, 1, 6, 8, 9, 5, 7]
[4, 5, 1, 6, 0, 2, 3, 8, 7]
[5, 4, 6, 7, 2, 0, 1, 3]
[6, 7, 5, 8, 3, 9, 0]
[7, 6, 8, 4, 9, 1]
[8, 9, 7, 5, 10]
[9, 8, 10, 11]
[10, 11, 9]
[11, 10]
[12]
...
		

References

  • Eric Friedman, Scott M. Garrabrant, Ilona K. Phipps-Morgan, A. S. Landsberg and Urban Larsson, Geometric analysis of a generalized Wythoff game, in Games of no Chance 5, MSRI publ. Cambridge University Press, date?

Crossrefs

Programs

  • PARI
    See Links section.