Exponential Riordan array [1+x*arctanh(x), x].

Terms

a(0) =1a(1) =0a(2) =1a(3) =2a(4) =0a(5) =1a(6) =0a(7) =6a(8) =0a(9) =1a(10) =8a(11) =0a(12) =12a(13) =0a(14) =1a(15) =0a(16) =40a(17) =0a(18) =20a(19) =0a(20) =1a(21) =144a(22) =0a(23) =120a(24) =0a(25) =30a(26) =0a(27) =1a(28) =0a(29) =1008