English
If each component α_i has a MeasurableConstSMul by M, then the space of functions ∀ i, α_i has a MeasurableConstSMul by M.
Русский
Если каждый компонент пространства α_i имеет измеримое константное умножение M, то функциональное пространство ∀ i, α_i имеет такое же свойство.
LaTeX
$$$\text{MeasurableConstSMul } M (\prod_i α_i)$$$
Lean4
@[to_additive]
instance instMeasurableConstSMul {ι : Type*} {α : ι → Type*} [∀ i, SMul M (α i)] [∀ i, MeasurableSpace (α i)]
[∀ i, MeasurableConstSMul M (α i)] : MeasurableConstSMul M (∀ i, α i) where
measurable_const_smul _ := measurable_pi_iff.2 fun i ↦ (measurable_pi_apply i).const_smul _