GAP 4.8.9 installation with standard packages -- copy to your CoCalc project to get it

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<Verb>Centre(M):: GOuterGroup --> GOuterGroup</Verb><P/>
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<P/> 
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Inputs a <M>G</M>-outer group  <M>M</M> and returns its group-theoretic centre
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as a <M>G</M>-outer group.
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