Number of weighted lattice paths in L_n having no (1,0)-steps at level 0. The members of L_n are paths of weight n that start at (0,0) , end on 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.
A182894
Number of weighted lattice paths in L_n having no (1,0)-steps at level 0. The members of L_n are paths of weight n that start at (0,0) , end on 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.
Terms
- a(0) =1a(1) =0a(2) =0a(3) =2a(4) =2a(5) =4a(6) =12a(7) =24a(8) =54a(9) =130a(10) =300a(11) =706a(12) =1686a(13) =4028a(14) =9686a(15) =23426a(16) =56866a(17) =138584a(18) =338940a(19) =831508a(20) =2045736a(21) =5046240a(22) =12477290a(23) =30919122a(24) =76774382a(25) =190995224a(26) =475979602a(27) =1188125394a(28) =2970282794a(29) =7436232760
External references
- oeis: A182894