Column 0 of triangle A109282.

Terms

a(0) =1a(1) =1a(2) =3a(3) =15a(4) =96a(5) =735a(6) =6447a(7) =63120a(8) =677739a(9) =7878921a(10) =98216466a(11) =1302951903a(12) =18283530882a(13) =270031107630