English
For x,y in cocycles2(A), H2π A x = H2π A y iff x−y lies in coboundaries2(A).
Русский
Для x,y из cocycles2(A) выполняется, что H2π A x = H2π A y тогда и только тогда, когда x−y лежит в coboundaries2(A).
LaTeX
$$H2π_A x = H2π_A y \Leftrightarrow x - y \in coboundaries_2(A)$$
Lean4
/-- Given a `k`-linear `G`-representation `A`, this is the chain complex `(A ⊗[k] P)_G`, where
`P` is the bar resolution of `k` as a trivial representation. -/
@[deprecated "Use `(barComplex k G).coinvariantsTensorObj A` instead." (since := "2025-06-17")]
abbrev coinvariantsTensorBarResolution [DecidableEq G] :=
(((coinvariantsTensor k G).obj A).mapHomologicalComplex _).obj (barComplex k G)