Generalized Mayer‑Vietoris for colimits over finite posets of CW‑complexes – mathoverflow.net
Y.Wei
I am trying to find a way to compute the cohomology ring of a space of the form $X:=\mathrm{colim}_{I}X_i$.
Here are the properties for this diagram of spaces:
The index set $I$ is a finite poset.
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