Riordan matrix (g(x),x*g(x)), where g(x) = (1-x-sqrt(1-2*x-3*x^2-4*x^3))/(2*x^2*(1+x)).

Terms

a(0) =1a(1) =1a(2) =1a(3) =2a(4) =2a(5) =1a(6) =5a(7) =5a(8) =3a(9) =1a(10) =12a(11) =14a(12) =9a(13) =4a(14) =1a(15) =31a(16) =38a(17) =28a(18) =14a(19) =5a(20) =1a(21) =83a(22) =106a(23) =84a(24) =48a(25) =20a(26) =6a(27) =1a(28) =227a(29) =301