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Groups and FieldsHardDirect Products and Finite Abelian Groups

Direct Products and Finite Abelian Groups · Hard problem

The group U(16)U(16) of units mod 1616 is isomorphic to Z4×Z2\mathbb Z_4 \times \mathbb Z_2. How many elements of order 66 does U(16)×Z3U(16) \times \mathbb Z_3 have?