Column 0 of triangle A135080.

Terms

a(0) =1a(1) =1a(2) =2a(3) =8a(4) =50a(5) =436a(6) =4912a(7) =68098a(8) =1122952a(9) =21488640a(10) =468331252a(11) =11456367820a(12) =310888085872