Triangle read by rows: T(n,k) is number of paths from (0,0) to (3n,0) that stay in the first quadrant (but may touch the horizontal axis), consisting of steps u=(1,1), d=(1,-2) and have k peaks (i.e., ud's).
A108767
Triangle read by rows: T(n,k) is number of paths from (0,0) to (3n,0) that stay in the first quadrant (but may touch the horizontal axis), consisting of steps u=(1,1), d=(1,-2) and have k peaks (i.e., ud's).
Terms
- a(0) =1a(1) =1a(2) =2a(3) =1a(4) =6a(5) =5a(6) =1a(7) =12a(8) =28a(9) =14a(10) =1a(11) =20a(12) =90a(13) =120a(14) =42a(15) =1a(16) =30a(17) =220a(18) =550a(19) =495a(20) =132a(21) =1a(22) =42a(23) =455a(24) =1820a(25) =3003a(26) =2002a(27) =429a(28) =1a(29) =56
External references
- oeis: A108767