The existence of near-Skolem and hooked near-Skolem sequences
نویسندگان
چکیده
منابع مشابه
The Existence of Two New Classes of Near-Skolem Type Sequences
Let m,n be two positive integers, m ≤ n. An m-near-Skolem sequence of order n and defect m is a sequence m − Sn = (s1, s2, · · · , s2n−2) of 2n − 2 non-negative integers such that the following conditions hold: 1. for each k ∈ {1, 2, · · · ,m−1,m+1, · · · , n} there exist exactly two elements si, sj ∈ m − Sn such that si = sj = k 2. if si = sj = k, then |i − j| = k For example, (4, 1, 1, 2, 4, ...
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We introduce indecomposable (hooked) Skolem sequences and we show their existence for all admissible orders. We then introduce a new construction for two-fold triple systems from two-fold Skolem sequences, and use this to motivate the concept of a two-fold Rosa sequence, whose existence we show for all admissible orders.
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ژورنال
عنوان ژورنال: Discrete Mathematics
سال: 1994
ISSN: 0012-365X
DOI: 10.1016/0012-365x(92)00327-n