Triangle read by rows: T(n,k) is the number of weighted lattice paths B(n) having k HH's. B(n) is the set of lattice paths of weight n that start in (0,0), end on the horizontal axis and never go below this axis, whose steps are of the following four kinds: a (1,0)-step h of weight 1; a (1,0)-step H of weight 2; a (1,1)-step u of weight 2; a (1,-1)-step d of weight 1. The weight of a path is the sum of the weights of its steps.

A246183

Triangle read by rows: T(n,k) is the number of weighted lattice paths B(n) having k HH's. B(n) is the set of lattice paths of weight n that start in (0,0), end on the horizontal axis and never go below this axis, whose steps are of the following four kinds: a (1,0)-step h of weight 1; a (1,0)-step H of weight 2; a (1,1)-step u of weight 2; a (1,-1)-step d of weight 1. The weight of a path is the sum of the weights of its steps.

Terms

    a(0) =1a(1) =1a(2) =2a(3) =4a(4) =7a(5) =1a(6) =15a(7) =2a(8) =33a(9) =3a(10) =1a(11) =71a(12) =9a(13) =2a(14) =158a(15) =23a(16) =3a(17) =1a(18) =357a(19) =54a(20) =10a(21) =2a(22) =812a(23) =136a(24) =26a(25) =3a(26) =1a(27) =1869a(28) =338a(29) =63

External references