Fishburn permutations are in bijection with several important combinatorial structures including interval orders.In this paper,we use the method of generating trees to enumerate two classes of pattern-avoiding Fishbur...Fishburn permutations are in bijection with several important combinatorial structures including interval orders.In this paper,we use the method of generating trees to enumerate two classes of pattern-avoiding Fishburn permutations subject to 7 classical statistics simultaneously.The classes of our interest are(321,312)-avoiding and(321,4123)-avoiding Fishburn permutations.The statistics of our interest are ascents,descents,inversions,right-to-left maxima,right-to-left minima,left-to-right maxima and left-to-right minima.Our results generalize a result by Egge.展开更多
基金National Natural Science Foundation of China(Grant No.12171362)。
文摘Fishburn permutations are in bijection with several important combinatorial structures including interval orders.In this paper,we use the method of generating trees to enumerate two classes of pattern-avoiding Fishburn permutations subject to 7 classical statistics simultaneously.The classes of our interest are(321,312)-avoiding and(321,4123)-avoiding Fishburn permutations.The statistics of our interest are ascents,descents,inversions,right-to-left maxima,right-to-left minima,left-to-right maxima and left-to-right minima.Our results generalize a result by Egge.