Riordan array (1,x(1-x)^2).

Terms

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