1,2

Size of optimal single-error-correcting code for Z-channel.

S. Butenko, P. Pardalos, I. Sergienko, V. P. Shylo and P. Stetsyuk, Estimating the size of correcting codes using extremal graph problems, in Optimization: Structure and Applications, edited by Charles Pearce, Kluwer, to appear, 2003.

T. Etzion, New lower bounds for asymmetric and unidirectional codes, IEEE Trans. Inform. Theory, 37 (1991), 1696-1705.

J. H. Weber, Bounds and Constructions for Binary Block Codes Correcting Asymmetric or Unidirectional Errors, Ph. D. Thesis, Tech. Univ. Delft, 1989.

J. H. Weber, C. de Vroedt and D. E. Boekee, Bounds and constructions for binary codes of length less than 24 and asymmetric distance less than 6, IEEE Trans. Inform. Theory, 34 (1988), 1321-1332.

Etzion, Tuvi and Ostergard, Patric R. J., Greedy and heuristic algorithms for codes and colorings, IEEE Transactions on Information Theory, 44 (1998), 382-388.

N. J. A. Sloane, Challenge Problems: Independent Sets in Graphs

Sequence in context: A115868 A103299 A154779 this_sequence A129860 A028408 A037163

Adjacent sequences: A010098 A010099 A010100 this_sequence A010102 A010103 A010104

nonn,nice,hard

N. J. A. Sloane (njas(AT)research.att.com).

Next 3 terms are known to be in the range 112-117, 198-210 and 379-410 respectively.