cochain complex

cochain complex

[′kō‚chān ′käm‚pleks]
(mathematics)
A sequence of Abelian groups Cn,- ∞ <>n < ∞,="" together="" with="" coboundary="" homomorphisms=""> n : CnC n +1such that δ n +1- δ n = 0.
References in periodicals archive ?
n](G,A) = [MATHEMATICAL EXPRESSION NOT REPRODUCIBLE IN ASCII] is called the symmetric cochain complex.
The first part of statement (i), statements (ii),(iii) and (v) are easy to verify since the equalities hold for maps of cochain complex in general, the without hypothesis that i is injective.
op] for a cochain complex C denotes the opposite chain complex that one obtains by reindexing in the opposite order and reversing all the arrows.