[seqfan] A259444

[Vladimir Shevelev]

I do not understand the definition of A259444:
"a(1)=2. For n>1, a(n) = smallest number > a(n-1)
such that, for all m,r<n, a(n) != a(m)^a(r)." 
The first terms 2, 3, 5, 6, 7, 10,...

Most likely, the author meant under ^ another operation.
But + is not suitable: indeed, if a(n) != a(m)+a(r), then
a(6)=10 is not suitable, since for m=2, r=5 we have a(m)+a(r)=a(6)
and also for m=3, r=3 we also have a(m)+a(r)=a(6).
What is the right definition?

Best regards,
Vladimir