A model for the relatively free graded algebra of block triangular   matrices with entries from a graded algebra
  Let G be a group and A be a G-graded algebra satisfying a polynomial identity. We buid up a model for the relative free G-graded algebra and we obtain, as an application, the "factoring" property for the T_G-ideals of block triangular matrices with entries from the finite dimensional Grassmann algebra E for some particular Z_2-grading. 
Thiago Castilho de Mello, Lucio Centrone
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