[FOM] Equivalence relation on sets of natural numbers

[Timothy Y. Chow]

Thanks to all who responded.  It seems that the most common notation for 
the equivalence relation itself is E_0, from the literature on Borel 
equivalence relations.

In addition to the responses on FOM, I received a few private email 
messages.  Kenny Easwaran pointed out that probabilists use the term "tail 
set" for sets of equivalence classes under E_0.  Franklin Vera Pacheco 
suggested the term "almost equal" for the equivalence relation.

Tim