Triangle read by rows: T(n,k) is the number of bargraphs of semiperimeter n having k valleys of width 1 (i.e., DHU configurations, where U=(0,1), H=(1,0), D=(0,-1)), (n>=2, k>=0).

A273721

Triangle read by rows: T(n,k) is the number of bargraphs of semiperimeter n having k valleys of width 1 (i.e., DHU configurations, where U=(0,1), H=(1,0), D=(0,-1)), (n>=2, k>=0).