TITLE: What does this notation mean for a squared matrix?
QUESTION [0 upvotes]: A is a square matrix
$A^n = A \cdot A\cdot$...$n$ times
What's $A^{2n}$?
$2A^n$ or $A \cdot A\cdot$...$2n$ times?

REPLY [3 votes]: It means $A\cdot A\cdot \dotsb$ $2n$ times, it's just a convenient way of making it clear that the power is even.
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