Riordan array (1/sqrt(1-2*x-3*x^2), 1/sqrt(1-2*x-3*x^2) -1).

Terms

a(0) =1a(1) =1a(2) =1a(3) =3a(4) =4a(5) =1a(6) =7a(7) =13a(8) =7a(9) =1a(10) =19a(11) =42a(12) =32a(13) =10a(14) =1a(15) =51a(16) =131a(17) =128a(18) =60a(19) =13a(20) =1a(21) =141a(22) =406a(23) =475a(24) =292a(25) =97a(26) =16a(27) =1a(28) =393a(29) =1247