Row sums of triangle defined in A059226.

Terms

a(0) =1a(1) =1a(2) =6a(3) =34a(4) =204a(5) =1290a(6) =8486a(7) =57512a(8) =398882a(9) =2817790a(10) =20205084a(11) =146685686a(12) =1076065002a(13) =7964304176a(14) =59400014606a(15) =445991850330