almost identical sequences in OEIS

[Ralf Stephan]

> Has anyone previously seen an example of two sequences that are known 
> to be different, but the difference doesn't occur within the number of 
> terms that fit in the database?

Some examples:

%Y A004953 Differs from A004973 for first time at n=2889.
%Y A025646 Differs from A025661 at a(1881).
%Y A025647 Differs from A025653 at a(2805).
%Y A084500 Differs from A084557 first time at the 605th term, where A084500(605) = 130, while A084557(605) = 131. Cf. A084510, A084520.