Definition 55.3.2. We say two numerical types $n, m_ i, a_{ij}, w_ i, g_ i$ and $n', m'_ i, a'_{ij}, w'_ i, g'_ i$ are equivalent types if there exists a permutation $\sigma$ of $\{ 1, \ldots , n\}$ such that $m_ i = m'_{\sigma (i)}$, $a_{ij} = a'_{\sigma (i)\sigma (j)}$, $w_ i = w'_{\sigma (i)}$, and $g_ i = g'_{\sigma (i)}$.

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