For infinite sets, a complete matching may be impossible even if Hails condition is
Chapter 8, Problem 8.4.11(choose chapter or problem)
For infinite sets, a complete matching may be impossible even if Hails condition is passed. If the first row is all 1s and then every ai i1 = 1, show that any p rows have 1s in at least p columnsand yet there is no complete matching.
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