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Partition of Triples of Order 6k+5 into 6k+3 Optimal Packings and One Packing of Size 8k+4

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Abstract.

A (2,3)-packing on X is a pair (X,), where is a set of 3-subsets (called blocks) of X, such that any pair of distinct points from X occurs together in at most one block. For a (6k+5)-set X, an optimal partition of triples (denoted by OPT(6k+5)) is a set of 6k+3 optimal (2,3)-packings and a (2,3)-packing of size 8k+4 on X. Etzion conjectured that there exists an OPT(6k+5) for any positive integer k. In this paper, we construct such a system for any k≥1. This complete solution is based on the known existence results of S(3,4,v)s by Hanani and that of special S(3,{4,6},6m)s by Mills. Partitionable candelabra systems also play an important role together with an OPT(11) and a holey OPT(11).

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References

  1. Brouwer, A.E., Shearer, J.B., Sloane N.J.A., Smith, W.D.: A new table of constant weight codes. IEEE Trans. Inform. Theory IT 36, 1334–1380 (1990)

    Google Scholar 

  2. Cao, H., Ji, L., Zhu, L.: Large sets of disjoint packings on 6k+5 points. J. Combin. Theory (A) 108, 169–183 (2004)

    Google Scholar 

  3. Cao, H., Lei, J., Zhu, L.: Large sets of disjoint group-divisible designs with block size three and type 2n41. J. Combin. Designs 9, 285–296 (2001)

    Google Scholar 

  4. Cao, H., Lei, J., Zhu, L.: Further results on large sets of disjoint group-divisible designs with block size three and type 2n41. J. Combin. Designs 11, 24–35 (2003)

    Google Scholar 

  5. Cao, H., Lei, J., Zhu, L.: Constructions of large sets of disjoint group-divisible designs LS(2n41) using a generalization of *LS(2n). Preprint

  6. Chen, D., Lindner, C.C., Stinson, D.R.: Further results on large sets of disjoint group-divisible designs. Discrete Math. 110, 35–42 (1992)

    Google Scholar 

  7. Chen, D., Stinson, D.R.: Recent results on combinatorial constructions for threshold schemes. Australasian J. Combin. 1, 29–48 (1990)

    Google Scholar 

  8. Chen, D., Stinson, D.R.: On the construction of large sets of disjoint group divisible designs. Ars Combin. 35, 103–115 (1993)

    Google Scholar 

  9. Etzion, T.: Optimal partition for triples. J. Combin. Theory (A) 59, 161–176 (1992)

    Google Scholar 

  10. Etzion, T.: Partition of triples into optimal packings. J. Combin. Theory (A) 59, 269–284 (1992)

    Google Scholar 

  11. Hanani, H.: On quadruple systems. Canad. J. Math. 12, 145–157 (1960)

    Google Scholar 

  12. Hartman, A.: The fundamental constructions for 3-designs. Discrete Math. 124, 107–132 (1994)

    Google Scholar 

  13. Ji, L.: Existence of large sets of disjoint group-divisible designs with block size three and type 2n41. J. Combin. Designs. 13, 302–312 (2005)

    Google Scholar 

  14. Kirkman, T.P.: On a problem in combinations. Cambridge and Dublin Math. J. 2, 191–204 (1847)

    Google Scholar 

  15. Lei, J.: Completing the spectrm for LGDD(mv). J. Combin. Designs 5, 1–11 (1997)

    Google Scholar 

  16. Lei, J., Chang, Y.: Constructions for large sets of disjoint compatible packings on 6k+5 points. Discrete Math. (to appear)

  17. Lu, J.X.: On large sets of disjoint Steiner triple systems I, II, and III. J. Combin. Theory (A) 34, 140–146, 147–155, and 156–182 (1983)

    Google Scholar 

  18. Lu, J.X.: On large sets of disjoint Steiner triple systems IV, V, and VI. J. Combin. Theory (A) 37, 136–163, 164–188, and 189–192 (1984)

    Google Scholar 

  19. Mills, W.H.: On the covering of triples by quadruples. Congr. Numer. 10, 563–581 (1974)

    Google Scholar 

  20. Mills, W.H.: On the existence of H designs. Congr. Numer. 79, 129–141 (1990)

    Google Scholar 

  21. Mohácsy, H., Ray-Chaudhuri, D.K.: Candelabra systems and designs. J. Statist. Plann. Inference 106, 419–448 (2002)

    Google Scholar 

  22. Van Pul, C.L., Etzion, T.: New lower bounds for constant weight codes. IEEE Trans. Inform. Theory, IT-35, 1324-1329 (1989)

    Google Scholar 

  23. Schellenberg, P.J., Stinson, D.R.: Threshold schemes from combinatorial designs. JCMCC 5, 143–160 (1989)

    Google Scholar 

  24. Spencer, J.: Maximal consistent families of triples. J. Combin. Theory (A) 5, 1–8 (1968)

    Google Scholar 

  25. Teirlinck, L.: A completion of Lu's determination of the spectrum of large sets of disjoint Steiner triple systems. J. Combin. Theory (A) 57, 302–305 (1991)

    Google Scholar 

  26. Teirlinck, L.: Some new 2-resolvable Steiner quadruple systems. Des., Codes and Cryptogr. 4, 5–10 (1994)

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Correspondence to Lijun Ji.

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Research supported by Natural Science Foundation of Universities of Jiangsu Province under Grant 05KJB110111

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Ji, L. Partition of Triples of Order 6k+5 into 6k+3 Optimal Packings and One Packing of Size 8k+4. Graphs and Combinatorics 22, 251–260 (2006). https://doi.org/10.1007/s00373-005-0632-1

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