Lemma 4

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

Let C be a bounded complex of type $\mathscr{C}$ . If $H(C) = 0$ , one has $\chi(C) = 0$ . This follows from VIII, § 6, No. 1, cor. of Prop. 1.

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

Cited by

Nothing.

Nothing.