Hamilton decompositions of regular tournaments

We show that every sufficiently large regular tournament can a lmost completely be decomposed into edge-disjoint Hamilton cycles. More precisely, for each � > 0 every regular tournament G of sufficiently large ordern contains at least (1/2 �)n edge-disjoint Hamilton cycles. This gives an approximate solution to a conjecture of Kelly from 1968. Our result also extends to almost regular tournaments.

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