Triangle read by rows: T(n,k) is the number of weighted lattice paths in B(n) having k ascents. The members of B(n) are paths of weight n that start at (0,0), end on but never go below the horizontal axis, and whose steps are of the following four kinds: an (1,0)-step with weight 1, an (1,0)-step with weight 2, a (1,1)-step with weight 2, and a (1,-1)-step with weight 1. The weight of a path is the sum of the weights of its steps. An ascent is a maximal sequence of consecutive (1,1)-steps.

A246186

Triangle read by rows: T(n,k) is the number of weighted lattice paths in B(n) having k ascents. The members of B(n) are paths of weight n that start at (0,0), end on but never go below the horizontal axis, and whose steps are of the following four kinds: an (1,0)-step with weight 1, an (1,0)-step with weight 2, a (1,1)-step with weight 2, and a (1,-1)-step with weight 1. The weight of a path is the sum of the weights of its steps. An ascent is a maximal sequence of consecutive (1,1)-steps.

Terms

    a(0) =1a(1) =1a(2) =2a(3) =3a(4) =1a(5) =5a(6) =3a(7) =8a(8) =9a(9) =13a(10) =23a(11) =1a(12) =21a(13) =55a(14) =6a(15) =34a(16) =125a(17) =26a(18) =55a(19) =274a(20) =93a(21) =1a(22) =89a(23) =584a(24) =295a(25) =10a(26) =144a(27) =1218a(28) =861a(29) =60

External references