The 4-Schroeder numbers: a(n) = number of lattice paths (Schroeder paths) from (0,0) to (3n,n) with unit steps N=(0,1), E=(1,0) and D=(1,1) staying weakly above the line y = 3x.

A144097

The 4-Schroeder numbers: a(n) = number of lattice paths (Schroeder paths) from (0,0) to (3n,n) with unit steps N=(0,1), E=(1,0) and D=(1,1) staying weakly above the line y = 3x.

Terms

    a(0) =1a(1) =2a(2) =14a(3) =134a(4) =1482a(5) =17818a(6) =226214a(7) =2984206a(8) =40503890a(9) =561957362a(10) =7934063678a(11) =113622696470

External references