By making use of our generalization of Barrucand and
Cohn’s theory of principal factorizations in pure cubic fields and their Galois closures with 3 possible types to pure
quintic fields and their pure metacyclic normal
fields with 13 possible types, we compile
an extensive database with arithmetical invariants of the 900 pairwise
non-isomorphic fields N having
normalized radicands in the range 2≤D<103. Our classification is based on the Galois cohomology of the unit group UN, viewed as a module over
the automorphism group Gal(N/K) of N over the cyclotomic field K=Q(ξ5), by employing theorems of Hasse and Iwasawa on the Herbrand quotient of
the unit norm index (Uk:NN/K(UN)) by the number #(PN/K/PK) of primitive ambiguous principal
ideals, which can be interpreted as principal factors of the different DN/K. The precise structure of the F5-vector space of differential principal factors is expressed in terms of
norm kernels and central orthogonal idempotents. A connection with integral
representation theory is established via class number relations by Parry and
Walter involving the index of subfield units (UN:U0)
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