Column 1 of triangle A111536.

Terms

a(0) =1a(1) =2a(2) =8a(3) =44a(4) =296a(5) =2312a(6) =20384a(7) =199376a(8) =2138336a(9) =24936416a(10) =314142848a(11) =4252773824a(12) =61594847360a(13) =950757812864