for that I posted this : TP should preserve sequence similarity!
which should also take care of ORDER.
Algebraic way to preserve order is to shift the SDR before UNION i.e.
abc = a >> 2 + b >> 4 + c >> 6 + ...
cab = c >> 2 + a >> 4 + b >> 6 + ...
later you can compare/check containment using the numbers … i.e. 2 is pos 1 in a sequence.
a >> 2 in abc : True
a >> 2 in cab : False