Triangle read by rows: T(n,k) is the number of paths of length n with steps U=(1,1), D=(1,-1) and H=(1,0), starting at (0,0), staying weakly above the x-axis (i.e., left factors of Motzkin paths) and having k peaks (i.e., UDs), 0 <= k <= floor(n/2).
A132893
Triangle read by rows: T(n,k) is the number of paths of length n with steps U=(1,1), D=(1,-1) and H=(1,0), starting at (0,0), staying weakly above the x-axis (i.e., left factors of Motzkin paths) and having k peaks (i.e., UDs), 0 <= k <= floor(n/2).
Terms
- a(0) =1a(1) =2a(2) =4a(3) =1a(4) =9a(5) =4a(6) =21a(7) =13a(8) =1a(9) =50a(10) =40a(11) =6a(12) =121a(13) =118a(14) =27a(15) =1a(16) =296a(17) =340a(18) =106a(19) =8a(20) =730a(21) =965a(22) =381a(23) =46a(24) =1a(25) =1812a(26) =2708a(27) =1296a(28) =220a(29) =10
External references
- oeis: A132893