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advanced-linear-algebra

Gelfand's formula and when A^n converges to zero

taught

$\lVert A^n\rVert^{1/n}$ converges to $\rho(A)$ as $n\to\infty$, regardless of how badly $\lVert A\rVert$ itself overstated the matrix's growth rate at $n=1$ -- and $A^n\to 0$ exactly when $\rho(A)<1$.

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