Column 1 of triangle A127082.

Terms

a(0) =1a(1) =2a(2) =7a(3) =28a(4) =127a(5) =650a(6) =3737a(7) =23996a(8) =170866a(9) =1338578a(10) =11446714a(11) =106063630a(12) =1057817614a(13) =11288886056a(14) =128243813228