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.

A076833 Triangle T(n,k) read by rows giving number of inequivalent projective binary linear [n,k] codes (n >= 1, 1 <= k <= n).

Original entry on oeis.org

1, 0, 1, 0, 1, 1, 0, 0, 2, 1, 0, 0, 1, 3, 1, 0, 0, 1, 4, 4, 1, 0, 0, 1, 5, 8, 5, 1, 0, 0, 0, 6, 15, 14, 6, 1, 0, 0, 0, 5, 29, 38, 22, 7, 1, 0, 0, 0, 4, 46, 105, 80, 32, 8, 1, 0, 0, 0, 3, 64, 273, 312, 151, 44, 9, 1, 0, 0, 0, 2, 89, 700, 1285, 821, 266, 59, 10, 1, 0, 0, 0, 1, 112
Offset: 1

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Author

N. J. A. Sloane, Nov 21 2002

Keywords

Comments

A code is projective if all columns are distinct and nonzero.

Examples

			1; 0,1; 0,1,1; 0,0,2,1; 0,0,1,3,1; 0,0,1,4,4,1; 0,0,1,5,8,5,1; ...
		

References

  • D. Slepian, Some further theory of group codes. Bell System Tech. J. 39 1960 1219-1252.
  • H. Fripertinger and A. Kerber, in AAECC-11, Lect. Notes Comp. Sci. 948 (1995), 194-204.

Crossrefs

Cf. A076834 (row sums). Partial sums across rows gives triangle A091008.