Abstract
There are simple arithmetic conditions necessary for the complete bipartite graph Km,n to have a complete factorization by subgraphs which are made up of disjoint copies of Kp,q. It is conjectured that these conditions are also sufficient. In any factor the copies of Kp,q have two orientations depending which side of the bipartition the p-set lies. The balance ratio is the relative proportion, x:y of these where gcd(x,y)=1. In this paper, we continue the study of the unbalanced case (y > x) where p = 1, to show that the conjecture is true whenever y is sufficiently large. We also prove the conjecture for K1,4-factorizations.
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Martin, N. Unbalanced Star-Factorizations of Complete Bipartite Graphs II. Graphs and Combinatorics 23, 559–583 (2007). https://doi.org/10.1007/s00373-007-0753-9
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DOI: https://doi.org/10.1007/s00373-007-0753-9