Abstract
An LPDTS(ν) is a collection of 3(ν − 2) disjoint pure directed triple systems on the same set of ν elements. It is showed in Tian’s doctoral thesis that there exists an LPDTS(gn) for gn ≡ 0,4 (mod 6), ν ⩾ 4. In this paper, we establish the existence of an LPDTS(ν) for ν ≡ 1,3 (mod 6), ν > 3. Thus the spectrum for LPDTS(ν) is completely determined to be the set {ν:ν ≡ 0, 1 (mod 3), ν ⩾ 4}.
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Zhou, J., Chang, Y. & Ji, L. The spectrum for large sets of pure directed triple systems. SCI CHINA SER A 49, 1103–1127 (2006). https://doi.org/10.1007/s11425-006-2007-3
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DOI: https://doi.org/10.1007/s11425-006-2007-3