Talk:Better-quasi-ordering

The definition of the relation $$\triangleleft$$ is slightly incorrect. When restricted to the sequences of length 1, it gives the total relation. One would like it to be the natural strict order on natural number. One must take $$s\triangleleft t$$ iff there is $$u$$ such that $$s$$ is a strict initial segment of $$u$$ and $$t={}_*u$$.