**The index map of a cell.** For a cell ideal `J` of a concrete member and child quotients `B j ≅ R_j ⧸ Φ J j`, there is an injective `O`-algebra map `R ⧸ J → ∏ B j` with cokernel of length `d(d-1)/2`

Initializing...

**The index map of a cell.** For a cell ideal `J` of a concrete member and child quotients `B j ≅ R_j ⧸ Φ J j`, there is an injective `O`-algebra map `R ⧸ J → ∏ B j` with cokernel of length `d(d-1)/2` · Prove2Me