Riordan array (f(x),x*f(x)) where f(x) is the g.f. of A117641.

Terms

a(0) =1a(1) =0a(2) =1a(3) =1a(4) =0a(5) =1a(6) =3a(7) =2a(8) =0a(9) =1a(10) =11a(11) =6a(12) =3a(13) =0a(14) =1a(15) =42a(16) =23a(17) =9a(18) =4a(19) =0a(20) =1a(21) =167a(22) =90a(23) =36a(24) =12a(25) =5a(26) =0a(27) =1a(28) =684a(29) =365