Dear all, I enabled automatic dummy index renaming also for ncmuls. This was done by moving the class make_flat_inserter from expairseq.cpp to expairseq.h and using that same class also in ncmul.cpp. After this Vladimirs test program gives as output: [[1],[2],[3],[4]].symbol8*((ONE+[[t],[x],[y],[z]].i*e.i)*e.symbol8) Best wishes, Chris