Bourbaki

Corollary 2

Tag 0BZQ, permanent. Cite it as [Bourbaki, Tag 0BZQ].

General Topology, chapter VII, § 3. Infinite sums in the groups $\mathbf{R}^n$

If (xλ)λ∈L(x_\lambda)_{\lambda \in L} and (yμ)μ∈M(y_\mu)_{\mu \in M} are two summable families of points of Rn\mathbf{R}^n, then the family (xλ∣yμ)(x_\lambda | y_\mu) (cf. Chapter VI, § 2, no. 2) is summable in R\mathbf{R}, and we have

∑(λ,μ)∈L×M(xλ∣yμ)=(∑λ∈Lxλ|∑μ∈Myμ). \sum_{(\lambda, \mu) \in L \times M} (x_\lambda | y_\mu) = \left( \sum_{\lambda \in L} x_\lambda \middle| \sum_{\mu \in M} y_\mu \right).

Bourbaki puts the proof directly after the statement, so what is above is the statement and its proof together.

Cited by

Nothing.

Cites

Transcribed from the printed volume. Not translated.