a(n) = D(n,1)/2^n, where D(n,x) is triangle A098277.

A098279

a(n) = D(n,1)/2^n, where D(n,x) is triangle A098277.

Terms

    a(0) =1a(1) =2a(2) =10a(3) =98a(4) =1594a(5) =38834a(6) =1323658a(7) =60134210a(8) =3511695322a(9) =256306614866

External references