I saw the "math" built-in mentioned in one of the unit test resources (path2.n3) and tried it out but it doesn't seem to work:
@prefix math: <http://www.w3.org/2000/10/swap/math#>.
@prefix : <http://test#>.
{ (2 1) math:sum ?y. } => { :result :is ?y. }.
:result :is (2 1)!math:sum.
Using this query:
SELECT ?s WHERE { :result :is ?s. }
I'm applying the RdfsReasoner followed by the SimpleN3RulesReasoner.
It doesn't return anything for the implication and returns just a blank node for the second line. There's a similar kind of behaviour for the "string" built-in as well with concatenation.
Am I doing something wrong or is there currently no support for this?