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 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 (list; table; graph; refs; listen; history; text; internal format)
 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. LINKS H. Fripertinger, Isometry Classes of Codes 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: A109466 A259095 A326676 * A071676 A319933 A301570 Adjacent sequences:  A076830 A076831 A076832 * A076834 A076835 A076836 KEYWORD nonn,tabl AUTHOR N. J. A. Sloane, Nov 21 2002 STATUS approved

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Last modified January 19 06:37 EST 2020. Contains 331033 sequences. (Running on oeis4.)