Jürgen,
With gnu apl (svn 961 on Fedora 25, Intel(R) Core(TM) i7-6700
CPU), the residue function (∣) yields the following:5J3 ∣ 14J5 1J4 5J3 | 1J4 ¯4J1 5J3 | ¯4J1 ¯4J1 The above result means that two elements in the complete residue system (CSR) for mod 5J3 are equal, i.e. 1J4 = ¯4J1 mod 5J3, which is not allowed. None of the elements of a CSR can be equal modulo the CSR's basis. Regards, Fred
