Alphabeta Math

Finite Abelian Groups: Examples and Counterexamples

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✓ 8 results · all verified · 0 also independently AI-judged
Every result on this page is machine-checked by a proof checker and read in full and owner-audited; the judge is an additional, independent cross-model AI review of the proofs. The 8 not AI-judged were verified by owner audit (typically over a confirmed judge false positive), not failures.
1 · Prerequisites
2 · Logical flowchart

3 · Items

Example

The cyclic group of order six in elementary-divisor and invariant-factor forms

Example

The five abelian groups of order sixteen

Example

Successive p-multiple layers recover the summands of Cₚ² times C_p³ times C_p⁴²

Example

The six abelian groups of order 360 in both classification forms

Example

Complements of a maximal cyclic subgroup in Cₚ× Cₚ need not be unique

Example

The unit group modulo one hundred is isomorphic to C₂₀ × C₂

Counterexample

The additive rationals do not decompose as a product of finite cyclic prime-power groups

False statement

FALSE: every finite group is a direct product of cyclic prime-power groups

Sources