GAP 4.8.9 installation with standard packages -- copy to your CoCalc project to get it
<!-- CD="cas" test -->
<OMOBJ xmlns="http://www.openmath.org/OpenMath" version="2.0">
<OMA>
<OMS cd="cas" name="assign"/>
<OMSTR>a</OMSTR>
<OMI> 1 </OMI>
</OMA>
</OMOBJ>
<OMOBJ xmlns="http://www.openmath.org/OpenMath" version="2.0">
<OMA>
<OMS cd="cas" name="retrieve"/>
<OMSTR>a</OMSTR>
</OMA>
</OMOBJ>
<OMOBJ xmlns="http://www.openmath.org/OpenMath" version="2.0">
<OMA>
<OMS cd="cas" name="native_statement"/>
<OMSTR>a := 3;</OMSTR>
</OMA>
</OMOBJ>
<OMOBJ xmlns="http://www.openmath.org/OpenMath" version="2.0">
<OMA>
<OMS cd="cas" name="native_statement"/>
<OMSTR>Size([1,2,3]);</OMSTR>
</OMA>
</OMOBJ>
<OMOBJ xmlns="http://www.openmath.org/OpenMath" version="2.0">
<OMA>
<OMS cd="cas" name="native_statement"/>
<OMSTR>quit;</OMSTR>
</OMA>
</OMOBJ>
<OMOBJ xmlns="http://www.openmath.org/OpenMath" version="2.0">
<OMA>
<OMS cd="cas" name="native_error"/>
</OMA>
</OMOBJ>
<OMOBJ xmlns="http://www.openmath.org/OpenMath" version="2.0">
<OMA>
<OMS cd="cas" name="native_output"/>
</OMA>
</OMOBJ>
<!-- character table examples -->
<OMOBJ xmlns="http://www.openmath.org/OpenMath" version="2.0">
<OMA>
<OMS cd="cas" name="native_statement"/>
<OMSTR>c := CharacterTable("V4");</OMSTR>
</OMA>
</OMOBJ>
<OMOBJ xmlns="http://www.openmath.org/OpenMath" version="2.0">
<OMA>
<OMS cd="cas" name="retrieve"/>
<OMSTR>c</OMSTR>
</OMA>
</OMOBJ>
<OMOBJ xmlns="http://www.openmath.org/OpenMath" version="2.0">
<OMA>
<OMS cd="cas" name="native_statement"/>
<OMSTR>c := CharacterTable("S3");</OMSTR>
</OMA>
</OMOBJ>
<OMOBJ xmlns="http://www.openmath.org/OpenMath" version="2.0">
<OMA>
<OMS cd="cas" name="native_statement"/>
<OMSTR>c := CharacterTable("fooey);</OMSTR>
</OMA>
</OMOBJ>
<!-- this tests the security feature -->
<OMOBJ xmlns="http://www.openmath.org/OpenMath" version="2.0">
<OMA>
<OMS cd="cas" name="native_statement"/>
<OMSTR>c := READ("fooey");</OMSTR>
</OMA>
</OMOBJ>
<OMOBJ xmlns="http://www.openmath.org/OpenMath" version="2.0">
<OMA>
<OMS cd="cas" name="native_statement"/>
<OMSTR>c := CharacterTable("fooey");</OMSTR>
</OMA>
</OMOBJ>
<OMOBJ xmlns="http://www.openmath.org/OpenMath" version="2.0">
<OMA>
<OMS cd="cas" name="retrieve"/>
<OMSTR>c</OMSTR>
</OMA>
</OMOBJ>
<!-- end character table examples -->
<OMOBJ xmlns="http://www.openmath.org/OpenMath" version="2.0">
<OMA>
<OMS cd="cas" name="quit"/>
</OMA>
</OMOBJ>