Number array whose rows are the series reversions of x(1-x)/(1+x)^k, read by antidiagonals.

Terms

a(0) =1a(1) =1a(2) =1a(3) =1a(4) =2a(5) =2a(6) =1a(7) =3a(8) =6a(9) =5a(10) =1a(11) =4a(12) =13a(13) =22a(14) =14a(15) =1a(16) =5a(17) =23a(18) =67a(19) =90a(20) =42a(21) =1a(22) =6a(23) =36a(24) =156a(25) =381a(26) =394a(27) =132a(28) =1a(29) =7