# Show that do not exist $G$ [duplicate]

Possible Duplicate:
There does not exist a group $G$ such that $|G/Z(G)|=pq$ for $p,q$ prime.

Let $p$ and $q$ prime numbers, with $p<q$ and $p \nmid (q-1)$. Show that do not exist group $G$ where $$\left\lvert\frac{G}{Z(G)}\right\rvert=pq.$$

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## marked as duplicate by Douglas S. Stones, DonAntonio, David Wallace, Norbert, Noah SnyderOct 17 '12 at 10:53

This question has been asked before and already has an answer. If those answers do not fully address your question, please ask a new question.

Isn't this the same as math.stackexchange.com/questions/214480/… which you asked yesterday? –  Gerry Myerson Oct 17 '12 at 1:00

## 1 Answer

Use this Fact: If $G/Z(G)$ is cyclic, then G is abelian.

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You asked the very same question and you also wrote the very same comment. The answer, as it is, is enough for you to develop a solution. If there's something you don't understand then ask. –  DonAntonio Oct 17 '12 at 3:29
@JarbasDantasSilva What's the center of an abelian group? –  Alexander Gruber Oct 17 '12 at 4:04
the group...???????????? –  Jarbas Dantas Silva Oct 17 '12 at 16:14