Holey Schrr Oder Designs of Type 2 N U 1
نویسندگان
چکیده
A holey Schrr oder design of type h n 1 1 h n 2 2 h n k k (HSD(h n 1 1 h n 2 2 h n k k)) is equivalent to a frame idempotent Schrr oder quasigroup (FISQ(h n 1 1 h n 2 2 h n k k)) of order m with n i missing subquasigroups (holes) of order h i ; 1 i k, which are disjoint and spanning, that is , P 1ik n i h i = m. In this paper, we rst consider the existence of HSD(2 n u 1) for 1 u 4 and show that these HSDs exist if and only if n u+1 with the exception of (n; u) 2 f(2; 1); (3; 1); (3; 2)g. Then we investigate the existence of HSD(2 n u 1) for general u and prove that there exists an HSD(2 n u 1) for u 16 and n 5u=4] + 14.
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