论文信息 - SMALL UNIVERSAL FAMILIES OF GRAPHS ON ℵ ω + 1

SMALL UNIVERSAL FAMILIES OF GRAPHS ON ℵ ω + 1

We prove that it is consistent that אω is strong limit, 2אω is large and the universality number for graphs on אω+1 is small. The proof uses Prikry forcing with interleaved collapsing.

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