English
If IsLUB (Set.range fun s ↦ ∏ i ∈ s, f i) b, then HasProd f b.
Русский
Если IsLUB (Set.range fun s ↦ ∏ i ∈ s, f i) равно b, то HasProd f b.
LaTeX
$$IsLUB (Set.range fun s => ∏ i ∈ s, f i) b \\\\Rightarrow HasProd f b$$
Lean4
@[to_additive]
theorem hasProd_of_isLUB [CommMonoid α] [LinearOrder α] [CanonicallyOrderedMul α] [TopologicalSpace α] [OrderTopology α]
{f : ι → α} (b : α) (hf : IsLUB (Set.range fun s ↦ ∏ i ∈ s, f i) b) : HasProd f b :=
tendsto_atTop_isLUB (Finset.prod_mono_set' f) hf