The Globals of Some Subpseudovarieties of DA

Let be the pseudovariety of all finite monoids whose principal right ideals have a unique generator, let be its dual, and let . Using the word problem for free pro- monoids, it is shown that the bilateral semidirect product is local, where denotes the pseudovariety of all finite semilattices. The global of the pseudovariety where is also computed and it is shown that this join is not local.

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