Improvement of the Delsarte Bound for tau-Designs in Finite Polynomial Metric Spaces
نویسندگان
چکیده
In this paper the problem for the improvement of the Delsarte bound for τ -designs in finite polynomial metric spaces is investigated. First we distinguish the two cases of the Hamming and Johnson Qpolynomial metric spaces and give exact intervals, when the Delsarte bound is possible to be improved. Secondly, we derive new bounds for these cases. Analytical forms of the extremal polynomials of degree τ +2 for non-antipodal PMS and of degree τ +3 for antipodal PMS are given. The new bound is investigated in the following asymptotical process: in Hamming space when τ and n grow simultaneously to infinity in a proportional manner and in Johnson space when τ , w and n grow simultaneously to infinity in a proportional manner. In both cases, the new bound has better asymptotical behavior then the Delsarte bound.
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