0PM4 Proposition 28 For i,j∈ℤi,j\in\mathbb{Z} there is an equality of isomorphism classes of abelian groups ℋi,j(L0)=ℋi+2l,j+2l(L).{\cal H}^{i,j}(L_{0})={\cal H}^{i+2l,j+2l}(L). (155)