Hammocks arising from the auslander-reiten quiver of representation-directed algebras

Hammocks have been introduced bu Brenner in order to give a numerical criterion for a finite traslation quiver to be the Auslander-Reiten quiver of some representation-finite algebra.Ringel and Vossieck gave a combinatorial definition of hammocks,and determined the relationship between hammocks and representation of partially order sets(abbreviated to poset).An important role in studing representation theory of algebras in some combinatorial way is played by hammocks .In this note,we show a class of hammocks arising from the Auslander-Reiten quiver of representation-directed algebras,which generalize the result of reference[4]the National Education Commission and Natural Science Foundation of Fujian Provic