Triangle in A144385 with rows left-adjusted.

Terms

a(0) =1a(1) =1a(2) =1a(3) =1a(4) =1a(5) =3a(6) =7a(7) =10a(8) =10a(9) =1a(10) =6a(11) =25a(12) =75a(13) =175a(14) =280a(15) =280a(16) =1a(17) =10a(18) =65a(19) =315a(20) =1225a(21) =3780a(22) =9100a(23) =15400a(24) =15400a(25) =1a(26) =15a(27) =140a(28) =980a(29) =5565