Wilson's Theorem

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Wilson's Theorem


Theorem [1]

For any given graph G, there exists an integer N(G) (N(G) is exponentially large) such that if

  • n > N(G);
  • n(n-1) \equiv 0 \,({\rm mod \ }2|E(G)|); and
  • n-1 \equiv 0 \,({\rm mod \ }d) where d is the greatest common divisor of the degrees of the vertices in G,

then there exists a G-design of order n.

  1. Wilson, R. M. Decompositions of complete graphs into subgraphs isomorphic to a given graph, Proceedings of the Fifth British Combinatorial Conference (Univ. Aberdeen, Aberdeen, 1975), Congressus Numerantium, No. XV, Utilitas Math., Winnipeg, Man. 647–659 (1976).