mon linear matrix equations. Moreover, since the triangular matrix equations
considered also appear as frequent subproblems in solving Riccatitype matrix
equations, we foresee a great impact of our work in control theory applications.
ACKNOWLEDGMENTS
We thank Fred Gustavson and the colleagues in the Ume˚a HPC and Parallel
Computing Research Group for stimulating and fruitful discussions. Finally,
we thank Sven Hammarling and the referees for constructive comments on an
earlier version of this manuscript.
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