Column 2 of triangle A128567.

Terms

a(0) =1a(1) =14a(2) =117a(3) =813a(4) =4871a(5) =27743a(6) =151208a(7) =804065a(8) =4185683a(9) =21472005a(10) =108766010a(11) =545507633a(12) =2712801330a(13) =13394412999a(14) =65722444172a(15) =320721839860