Riordan array (1/(1+x*c(x)), x*c(x)) where c(x) is the g.f. of Catalan numbers (A000108).

Terms

a(0) =1a(1) =-1a(2) =1a(3) =0a(4) =0a(5) =1a(6) =-1a(7) =1a(8) =1a(9) =1a(10) =-2a(11) =2a(12) =3a(13) =2a(14) =1a(15) =-6a(16) =6a(17) =8a(18) =6a(19) =3a(20) =1a(21) =-18a(22) =18a(23) =24a(24) =18a(25) =10a(26) =4a(27) =1a(28) =-57a(29) =57