Erdős Problem #1167 — Stepping Down Cardinal Partition Relations

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Let r∈Nr\in\mathbb N with r≥2r\ge2, let λ\lambda be an infinite cardinal, let γ\gamma be an ordinal with γ≥2\gamma\ge2, and let (κα)α<γ(\kappa_\alpha)_{\alpha<\gamma} be a family of cardinals. For cardinals μ\mu and (να)α<γ(\nu_\alpha)_{\alpha<\gamma}, write

μ⟶(να)α<γs\mu\longrightarrow(\nu_\alpha)_{\alpha<\gamma}^{s}

to mean that for every set XX of cardinality μ\mu and every coloring c:[X]s→γc:[X]^s\to\gamma of the ss-element subsets of XX, there exist an index α<γ\alpha<\gamma and a subset H⊆XH\subseteq X of cardinality να\nu_\alpha such that every ss-element subset of HH has color α\alpha. Here κα+1\kappa_\alpha+1 uses cardinal addition. Is it true that

2λ⟶(κα+1)α<γr+1⟹λ⟶(κα)α<γr?2^\lambda\longrightarrow(\kappa_\alpha+1)_{\alpha<\gamma}^{r+1} \quad\Longrightarrow\quad \lambda\longrightarrow(\kappa_\alpha)_{\alpha<\gamma}^{r}?
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