Column 1 of triangle A132845.

Terms

a(0) =1a(1) =2a(2) =9a(3) =42a(4) =270a(5) =1785a(6) =13657a(7) =108606a(8) =943677a(9) =8534290a(10) =82099523a(11) =819569205a(12) =8575756709a(13) =92782439316