A triangle related to the GF(z) formulas of the rows of the ED1 array A167546.

Terms

a(0) =1a(1) =1a(2) =2a(3) =2a(4) =6a(5) =2a(6) =6a(7) =24a(8) =4a(9) =8a(10) =24a(11) =120a(12) =0a(13) =48a(14) =24a(15) =120a(16) =720a(17) =-120a(18) =384a(19) =72a(20) =144a(21) =720a(22) =5040a(23) =-1680a(24) =3696a(25) =-432a(26) =1296a(27) =720a(28) =5040a(29) =40320