Total number of nodes summed over all lattice paths from (0,0) to (n,0) that do not go below the x-axis or above the diagonal x=y and consist of steps U=(1,1), D=(1,-1), H=(1,0) and S=(0,1).

A286760

Total number of nodes summed over all lattice paths from (0,0) to (n,0) that do not go below the x-axis or above the diagonal x=y and consist of steps U=(1,1), D=(1,-1), H=(1,0) and S=(0,1).

Terms

    a(0) =1a(1) =2a(2) =10a(3) =42a(4) =214a(5) =1098a(6) =5978a(7) =33190a(8) =189078a(9) =1093490a(10) =6414714a(11) =38027030a(12) =227489950a(13) =1370980490a(14) =8314674202a(15) =50696630838a(16) =310541818382

External references