Triangle T(n,k) read by rows giving number of underdiagonal lattice paths from (0,0) to (n,k) using steps R=(1,0), V=(0,1) and D=(2,1).

A071945

Triangle T(n,k) read by rows giving number of underdiagonal lattice paths from (0,0) to (n,k) using steps R=(1,0), V=(0,1) and D=(2,1).

Terms

    a(0) =1a(1) =1a(2) =1a(3) =1a(4) =3a(5) =3a(6) =1a(7) =5a(8) =9a(9) =9a(10) =1a(11) =7a(12) =19a(13) =31a(14) =31a(15) =1a(16) =9a(17) =33a(18) =73a(19) =113a(20) =113a(21) =1a(22) =11a(23) =51a(24) =143a(25) =287a(26) =431a(27) =431a(28) =1a(29) =13

External references