grandes-ecoles 2016 QVI.A

grandes-ecoles · France · centrale-maths1__mp Matrices Matrix Power Computation and Application
Let $A$ be an imprimitiv matrix with coefficient of imprimitivity $p \geqslant 2$.
For any integer $m$ that is not a multiple of $p$, show that the diagonal of $A^m$ is identically zero. One can be interested in the trace of $A^m$.
Deduce that the result of question IV.B.3 no longer holds if $A$ is imprimitiv.
Let $A$ be an imprimitiv matrix with coefficient of imprimitivity $p \geqslant 2$.

For any integer $m$ that is not a multiple of $p$, show that the diagonal of $A^m$ is identically zero. One can be interested in the trace of $A^m$.

Deduce that the result of question IV.B.3 no longer holds if $A$ is imprimitiv.