Hello, I encountered the problem that after calling simplify_indexed, some of the symbols used in indices appeared three times in some of the terms. Before simplify_indexed was called this was not the case. The problem seems to be that in the function rename_dummy_indices, indices are compared by calling ex_is_equal on two of them. However, it may happen that the indices that are compared this way have the same value but different dimension. If that happens, they are considered not to be the same, but as far as dummy indices renaming is concerned but I think they should be considered the same. The attached patch is supposed to fix this. Greetings, Chris Dams