VOOZH about

URL: https://oeis.org/A076833

⇱ A076833 - OEIS

login
A076833
Triangle T(n,k) read by rows giving number of inequivalent projective binary linear [n,k] codes (n >= 1, 1 <= k <= n).
2
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
1,9
COMMENTS
A code is projective if all columns are distinct and nonzero.
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.
EXAMPLE
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; ...
CROSSREFS
Cf. A076834 (row sums). Partial sums across rows gives triangle A091008.
Sequence in context: A362763 A259095 A326676 * A071676 A319933 A335964
KEYWORD
nonn,tabl
AUTHOR
N. J. A. Sloane, Nov 21 2002
STATUS
approved