Triangle read by rows: T(n,k) is the number of ordered triples of n-permutations with exactly k common descents, n>=0, 0<=k<=max(0,n-1).

A334394

Triangle read by rows: T(n,k) is the number of ordered triples of n-permutations with exactly k common descents, n>=0, 0<=k<=max(0,n-1).

Terms

    a(0) =1a(1) =1a(2) =7a(3) =1a(4) =163a(5) =52a(6) =1a(7) =8983a(8) =4499a(9) =341a(10) =1a(11) =966751a(12) =660746a(13) =98256a(14) =2246a(15) =1a(16) =179781181a(17) =155729277a(18) =35677082a(19) =2045282a(20) =15177a(21) =1a(22) =53090086057a(23) =55690144728a(24) =17446464519a(25) =1754605504a(26) =42658239a(27) =104952a(28) =1a(33) =84058424389

External references